Previous seminars

Recent advances in quantum computers are demonstrating the ability to solve problems at a scale beyond brute force classical simulation. As such, a widespread interest in quantum algorithms has developed in many areas, with optimization being one of the most pronounced domains. Across computer science and physics, there are a number of different approaches for major classes of optimization problems, such as combinatorial optimization, convex optimization, non-convex optimization, and stochastic extensions. This work draws on multiple approaches to study quantum optimization. Provably exact versus heuristic settings are first explained using computational complexity theory -- highlighting where quantum advantage is possible in each context. Then, the core building blocks for quantum optimization algorithms are outlined to subsequently define prominent problem classes and identify key open questions that, if answered, will advance the field. The effects of scaling relevant problems on noisy quantum devices are also outlined in detail, alongside meaningful benchmarking problems. We underscore the importance of benchmarking by proposing clear metrics to conduct appropriate comparisons with classical optimization techniques. Lastly, we highlight two domains - finance and sustainability - as rich sources of optimization problems that could be used to benchmark, and eventually validate, the potential real-world impact of quantum optimization. The talk is based in part on our survey in Nature Reviews Physics (https://doi.org/10.1038/s42254-024-00770-9), and our earlier papers in Quantum (https://doi.org/10.22331/q-2024-10-10-1495, https://doi.org/10.22331/q-2021-06-17-479). We will also provide a preview of Qiskit Optimization (https://qiskit-community.github.io/qiskit-optimization/).

Solving chemistry problems has often been advocated as a short terms goal for near future quantum computers. In this talk, I will look at these claims in some details and show the likely limits of the proposed approaches. In a second part, I will show that on the other hand a lot is happening on the classical algorithms side. I will discuss in particular our own development using tensor network orbitals. 

Spintronics is a field of research that harnesses the electron’s spin to create novel materials with exotic properties and devices especially those for storing digital data that is the lifeblood of many of the most valuable companies today. Spintronics has already had two major technological successes with the invention and application of spin-valve magnetic field sensors that allowed for more than a thousand-fold increase in the storage capacity of magnetic disk drives that store ~70% of all digital data today. Just recently, after almost a 25-year exploration and development period, a high performance nonvolatile Magnetic Random Access Memory, that uses magnetic tunnel junction memory elements, became commercially available. A novel spintronics memory-storage technology, Magnetic Racetrack Memory is on track to become the third major success of spintronics. Racetrack Memory is a non-volatile memory in which data is encoded in mobile chiral domain walls that are moved at high speeds by spin currents to and through along synthetic antiferromagnetic racetracks [1-3]. In this lecture I will introduce the basic physics and especially the novel atomically-engineered materials that make possible these three spintronic technologies. 

1 Parkin, S. S. P., Hayashi, M. & Thomas, L. Magnetic Domain-Wall Racetrack Memory. Science 320, 190-194 (2008). https://doi.org/10.1126/science.1145799

2 Jeon, J.-C., Migliorini, A., Yoon, J., Jeong, J. & Parkin, S. S. P. Multi-core memristor from electrically readable nanoscopic racetracks. Science 386, 315-322 (2024). https://doi.org/10.1126/science.adh3419

3 Farinha, A. M. A., Yang, S.-H., Yoon, J., Pal, B. & Parkin, S. S. P. Interplay of geometrical and spin chiralities in 3D twisted magnetic ribbons. Nature 639, 67–72 (2025). https://doi.org/10.1038/s41586-024-08582-8

Magnetization Dynamics in Artificial Spin Ice Based on Magnetic Tunnel Junctions

Connor Sullivan 1 and Sara A. Majetich 2

1. Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, USA.

2. Department of Physics, Carnegie Mellon University, Pittsburgh, USA.

Magnetic frustration significantly alters the dynamics of magnetostatically coupled nanomagnets. Artificial Spin Ice (ASI), simultaneous frustration of multiple nanomagnets leads to complex and long-range behavior [1, 2], including nonequilibrium excitations known as Emergent Magnetic Monopoles (EMMs). Here the nanomagnets are free layers of magnetic tunnel junctions (MTJs) with in-plane magnetization and a pinned synthetic antiferromagnet (SAF) fixed layer. This enables faster dynamics and has potential for electrical rather than magnetic field control. The focus in this work is on square lattice ASI made from circular 60 nm diameter MTJs with a 30 nm spacing. Tunnel magnetoresistance (TMR) is measured through individual devices using direct contact to a conductive atomic force microscopy (C-AFM) tip that is biased relative to the substrate. The spontaneous magnetization directions of the MTJs follow a pattern similar to that of square lattice ASI made from larger elongated nanomagnets [1] except that the moment directions vary on a millisecond time scale. The symmetry is broken by a small (8 Oe) coupling field between the free layer nanomagnets and unpatterned fixed layer. This symmetry breaking also means that half of the nanomagnets have moments parallel (0°) or antiparallel (180°) to an easy axis, and show typical two level telegraphing, while the other half have moments more or less aligned along the hard axis. The hard axis nanomagnets have time-dependent canting, with an average angle of ± 90° but with significant deviations that depend on the local field due to neighboring nanomagnets. Analysis of the distribution of dwell time reveals the importance of the spin canting in long-range coupling of nanomagnets that leads to short-term memory of the ensemble. Strategies for using MTJ-ASI in passive neural networks are discussed. 

References

[1] R. F. Wang, et al., Nature 439, 303 (2006).

[2] E. Mengotti, et al., Nature Physics 7, 68 (2011).

Quantum many-body theories, including diagrammatic perturbation theory and non-perturbative embedding theories, are rigorous and well-developed theories used to describe the physics of many interacting particles in solids. They are typically applied to lattice model systems that capture only the essential degrees of freedom.

This talk will summarize recent progress on solving the many-body problem ab-initio, i.e. without adjustable parameters and without the construction of effective low-energy models, using diagrammatic and embedding theories. We will show how algorithmic and computational advances have enabled the adaptation of tools that were previously only available on lattice models to real-materials simulations, and how these simulations now avoid several common uncontrolled approximations. A path towards controlled and adaptive many-body simulations is outlined.

In this talk, we study the propagation, entanglement, and entropy of quantum information using 3x3 and 4x4 arrays of superconducting qubits that emulate the two-dimensional (2D) hard-core Bose-Hubbard model. The 2D arrays feature site-selective, simultaneous control and readout of all qubits. We highlight several recent experimental demonstrations using these arrays, including quantum random walks, Anderson and Wannier-Stark localization [1], the differentiation between area-law and volume-law entanglement scaling in these lattices [2], Aharonov-Bohm caging [3], and the emulation of flat-bands in 1D chains [4]. Time permitting, I will talk about recent improvements in control fidelity with fluxonium qubits at the 99.998% level for single-qubit gates [5].

[1] npj Quantum Information 8, 35 (2022) | arXiv:2107.05035 (2021)

[2] Nature 629, 561-566 (2024) | arXiv:2306.02571 (2023)

[3] Nature Physics 20, 1881-1887 (2024) | arXiv:2405.00873 (2024)

[4] arXiv:2410.07878 (2024)

[5] PRX Quantum 5, 040342 (2024) | arXiv:2406.08295 (2024)

The idea of synthetic dimensions is to use non-spatial degrees of freedom as if they are spatial dimensions to simulate high-dimensional Hamiltonians in low-dimensional physical platforms. The idea was originally proposed in ultracold atoms to use spin degrees of freedom as an additional dimension to realize topological Hamiltonians. The concept of synthetic dimensions was soon exported to the realm of photonics. Since then, the idea of synthetic dimensions has been successfully employed in both ultracold atoms and photonics to simulate various Hamiltonians of interest, especially topologically nontrivial Hamiltonians. In this talk, I will give an overview of the physics of synthetic dimensions, starting from its motivation and covering some of the most recent developments.

Graphene is ideally suited to expose it to strong optical fields: It absorbs only a small fraction of the light, allowing the electrons inside graphene to experience a strong optical field before damage. Based on this, we could show that we can drive electrons strongly in graphene - intraband motion and interband transitions are intricately coupled. We will show that, intriguingly, the electron dynamics is fully coherent. We could show Landau-Zener-Stückelberg-Majorana physics and even use this type of interferometry to measure band structure properties. What's more, we could also already show initial applications of this ultrafast driving: We could demonstrate a logic gate with input bits encoded in the waveforms of two laser pulses. This logic gate can, in principle, lay the foundation of petahertz electronics. In the last part of the talk we will show that we can dress graphene with a circular light pulse, driving it into a Floquet topological insulator state, hence a topologically non-trivial material. With another laser pulse, we can drive electrons inside of this state and observe the optical anomalous Hall effect, where the Berry curvature takes over the role of the magnetic field.

Synchrotron-based X-ray Magnetic Circular Dichroism is a measurement technique that has created a breakthrough in Magnetism. It is element sensitive, resolves spin and orbital magnetic moments, is extremely sensitive, allowing to study very small samples, and combined with varying temperatures and applied magnetic field allows to enter into the realm of Magnetic Phase transitions in solids, Nanomagnetism, Molecular Magnetism, Imaging or Time Resolution experiments.

In this talk, we shall introduce the constituent devices in a 3rd generation synchrotron, the XMCD  technique, the sum rules for data analysis, and some relevant general concepts.

Thereafter, some selected examples comprise permanent magnets and nanomagnetic materials, such as Co nanoparticles capped with noble metals, Au nanoparticles and Pt clusters. As a third group, we deal with molecular magnets, such as FeLa butterfly molecules, phthalocyanine thin films and molecular Cr wheels deposited on a substrate.

The imaginary time evolution of a quantum system allows one to access many vital quantities, including ground and thermal states. While our capacity to perform simulations of quantum systems is expected to be greatly increased by quantum computing, the present paradigm of quantum-circuit models restricts quantum algorithms to the implementation of unitary gates. This means that imaginary time evolution cannot be directly implemented in a quantum circuit. Consequently, the many simulation techniques predicated on imaginary time evolution cannot be imported into a quantum algorithmic setting. In this talk I will address this by introducing the concept of quantum dynamical emulation, a constructive method for mapping the solutions of non­unitary dynamics to a weighted set of unitary operations (the latter of which can be implemented in a quantum circuit). This allows for the derivation of a new correspondence between real and imaginary time, termed Imaginary Time Quantum Dynamical Emulation (ITQDE). Using ITQDE it is possible to not only to infer ground and thermal states, but also to resolve information about the complete Hamiltonian spectrum. From this a quantum algorithm for computing the spectra of quantum systems is developed, and its utility is demonstrated both through numerical simulation and quantum hardware implementations. Finally, I will highlight some of the broader connections of ITQDE to thermodynamics, and how it might be employed in this context.

This talk will focus on experimental search and discovery of novel forms of quantum order in metallic and insulating magnets, intercalated compounds, ferroelectric systems and multi-ferroic materials. Particularly discussed will be the pressure-induced superconductivity and critical phenomena in the vicinity of quantum phase transitions.

The US Army has a program to fund basic research projects for researchers outside the US, in a wide range of topics, including chemistry, physics, biology, computer science, materials, and more. The “Broad Agency Announcement” (or BAA) is the Army’s standing call for proposals covering these (and many other) topics. During this presentation, Dr. Brame will share the application process for the BAA, which starts with a simple 1-2 page pre-proposal, and the logistics of receiving funding from the US Army for basic and applied research. The purpose of this funding program is to contribute to scientific understanding and support publication of strong papers in peer-reviewed journals, and there are programs for both extremely fundamental science (with no obvious connection to military applications) and more applied technology development.
Dr. Gamble will continue the seminar by discussing current priority research areas related to the quantum sciences, including but not limited to foundational quantum mechanics important for quantum information science, quantum sensing and metrology, quantum computation, and distributed quantum information.  

Superconducting qubits have emerged as a leading platform for quantum computation and simulation, particularly for studying quantum dynamics on Noisy Intermediate-Scale Quantum (NISQ) processors. In a recent study [1], we explore the dynamics of charges and strings in (2+1)D lattice gauge theories, using these processors to directly image string behavior. We find two distinct regimes within the confining phase: in the weak confinement regime, the string exhibits strong transverse fluctuations, while in the strong confinement regime, these fluctuations are effectively suppressed. In another study [2], we observe a novel form of localization in quantum many-body systems in one and two dimensions. Despite the absence of disorder, perturbations do not spread, even when both the evolution generator and initial states are fully translationally invariant. These results demonstrate that NISQ processors – in the absence of fully-fledged quantum processors – are valuable tools for probing non-equilibrium physics, offering critical insights into complex quantum dynamics. 

[1] Cochran et al., arxiv.org/abs/2409.17142

[2] Gyawali  et al., arxiv.org/abs/2410.06557

I will present recent theoretical and experimental results on: (i) subwavelength high-intensity vortices around holes in 2D wave systems: from polaritons to ocean waves, (ii) generation of the Bessel-type vortices, displacement-field skyrmions, and polarization Möbius strips in sound and water waves,  and  (iii) manipulation of floating particles using topologically structured water waves. 

Wolfram Language, known for its integration of symbolic and numerical computation, remains a cutting-edge platform even after four decades. Its unique notebook interface enhances user experience, making it ideal for diverse applications. With the introduction of the Wolfram Quantum Framework, the platform extends its capabilities to quantum computation, supporting algorithms, hardware interactions, and simulations in finite vector spaces. It also enables exploration of open quantum systems, including deterministic and stochastic dynamics. Additionally, the framework offers tools for foundational studies, such as generalized probability theory and quantum phase space analysis. This talk will provide an overview of these features. 

Essentially any material around us harbors some quantum fluctuations, which contain markers of relevant many-body physics as well as potential quantum utility. I will review our recent ideas to unravel and then harvest these quantum fluctuations, with a focus on magnetic materials and quantum color centers (such as nitrogen-vacancy impurities). Recent experiments on using color-center qbits as spectrally-resolved sensors of spin transport and magnetic dynamics demonstrate their strong coupling with a range of 2D materials. Inspired in part by the ideas from quantum optics and practical developments in spintronics, we thus suggest a natural integration of color-center qbits with driven magneto-electronic devices. Remarkably, classical dissipative drives can be used to switch and control scalable quantum entanglement within a proximal qbit ensemble, suggesting rich sensing and computational opportunities.

Recent progress in subwavelength optics is driven by the physics of optical resonances. This provides a novel platform for localization of light in subwavelength photonic structures and opens new horizons for metamaterial-enabled photonics, or metaphotonics. Recently emerged field of Mie-resonant metaphotonics (also called "Mie-tronics") employs resonances in high-index dielectric nanoparticles and dielectric metasurfaces and aiming for novel applications of the subwavelength optics and photonics,  benefiting from low material losses and optically-induced magnetic response. In this talk, I will review the recent advances in the fields of metamaterials, metaphotonics, and metasurfaces related to our research at ANU in Canberra.  

As the frontiers of artificial intelligence advance more rapidly than ever before, generative language models like GPT are already causing significant economic and social transformation. In addition to their remarkable performance on typical language tasks - such as generating text from a prompt - language models are being rapidly adopted as powerful predictive tools for studying quantum computers. In this talk, I will discuss the use of such models for learning states realized in existing experimental quantum simulators. I will show how language models are poised to become one of the most powerful computational tools in our arsenal for the design and characterization of today's quantum simulators and tomorrow's fault-tolerant computers.

The silicon metal-oxide-semiconductor transistor is the workhorse of the microelectronics industry. It is the building block of all major electronic information processing components such as microprocessors, memory chips and telecommunications microcircuits. By shrinking its size generation after generation, the computational performance, memory capacity and information processing speed have increased relentlessly. However, the process of miniaturization is bound to reach its fundamental physical limits in the next decades.

Paradoxically, silicon technology itself is a promising platform for quantum computing. Several recent demonstrations have shown single- and two-qubit gate fidelities exceeding the requirements for fault-tolerant thresholds[1–3]. Moreover, silicon quantum circuits present dense scaling potential [4,5] and can use advanced manufacturing [6,7] facilitating the integration with cryogenic classical electronics [8].

In this talk, I will review the field of silicon-based quantum computing going from the basic physics that govern spin qubits in this material, all the way to the technological implementation, the state-of-the-art and the scaling challenges ahead. Finally, I will present Quantum Motion's recent work on devices fabricated using 300-mm wafer processes, including exchange-driven spin-spin interactions, rapid characterisation of 1000+ quantum devices [9] and on-chip deep-cryogenic thermometry [10].

References

[1] X. Xue, Nature 601 343 (2022)

[2] A. Noiri, Nature 601 338 (2022)

[3] A. R. Mills Sci. Adv. 8, 14 (2022)

[4] M. Veldhorst, Nat. Commun. 8, 1766 (2017)

[5] O. Crawford, npj Quant Info (2023)

[6] R. Maurand Nat. Commun. 7, 13575 (2016)

[7] A. M. J. Zwerver, Nat Elect 5, 184 (2022)

[8] A. Ruffino, Nat Elect 5 53 (2022)

[9] E. Thomas, arvix:2310.20434 (2023)

[10] G. Noah, App Phys Rev 11, 021414 (2024)

Spin currents in the diffusive regime are an old story. They came into fashion in 1990s with the discovery of the phenomenon of giant magnetoresistance (GMR) that produced modern hard drive read heads and created a revolution in magnetic data storage, and with the Datta-Das spin transistor proposal that was not as successful. As device sizes continue to shrink, reaching tens of nanometers, ballistic and quantum transport regimes become more and more important. Yet diffusive spin currents are still able to produce examples of unexpected and appealing physical situations. In this tutorial-style talk I will present two of them:

  The first example considers pure spin injection into a dangling part of a circuit. Electric currents, upon which much of our intuition about currents is based, never enter dead ends of the wires. The reason for that is electric current conservation. Being non-conserved, spin currents can behave counter-intuitively and produce "counter-intuitive" phenomena.

  The second example considers the magnetoresistance of a single interface between a ferromagnet and a normal metal. Usually two interfaces, like in a spin valve, are needed to observe spin-related magnetoresistance. I will show how a combination of magnetic field and alternative current spin injection produces a magnetoresistance pattern on a single boundary. 

Recently we have demonstrated experimentally the implementation of a novel and universal method to increase the decoherence time of spins qubits [1] in systems with different anisotropies / symmetries / spin-orbit coupling and type of element. The method is based on Floquet engineering of spin qubits quasi-energies by adding a second microwave drive with a frequency commensurate to that of the main Rabi drive. Qualitatively, the increase in coherence time can be linked to dynamical sweet spots (level repulsion) in quasi-energy spectra. Quantitatively, we add insight using numerical simulations [2] aiming to clarify the actual physical processes that take place in the bath surrounding the qubit. We are also exploring the potential use of spin systems as quantum memories [3] and to that effect, we have performed spectroscopic and pulsed studies of S=7/2 Gd ions placed on a coplanar stripline superconducting resonator. In the weak coupling limit, continuous-wave spectroscopy of the cavity resonance perturbation allows us to detect the forbidden electro-nuclear transition of the 155,157Gd isotopes by applying a static field almost perpendicular to crystal c-axis [4]. By increasing the coupling of the spin ensemble to the resonator we observe spin-cavity dressed states with a large mode splitting of ~150 MHz. Numerical simulations based on Dicke model shows a strong hybridization of the first excited level in the presence of a photon and the second excited level with no photon as well as a strong perturbation of the spin ground state generated by photons.

[1] S. Bertaina, H. Vezin, H. De Raedt, and I. Chiorescu, Experimental protection of quantum coherence by using a phase-tunable image drive, Scientific Reports 10, 1 (2020)

[2] De Raedt, H.; Miyashita, S.; Michielsen, K.; Vezin, H.; Bertaina, S.U.; Chiorescu, I., Sustaining Rabi oscillations by using a phase-tunable image drive, European Physical Journal B, 95 (9), 158 (2022)

[3] M. Blencowe, Quantum computing: Quantum RAM, Nature 468, 44 (2010).

[4] Franco-Rivera, G.; Cochran, J.R.; Miyashita, S.; Bertaina, S.U.; Chiorescu, I., Strong Coupling of a Gd3+ Multilevel Spin System to an On-Chip Superconducting Resonator, Physical Review Applied, 19, 024067 (2023).

In quantum optics, atoms are usually approximated as point-like compared to the wavelength of the light they interact with. However, recent advances in experiments with artificial atoms built from superconducting circuits have shown that this assumption can be violated. Instead, these artificial atoms can couple to an electromagnetic field in a waveguide at multiple points, which are spaced wavelength distances apart. Such systems are called giant atoms. They have attracted increasing interest in the past few years (e.g., see the review in [1]), in particular because it turns out that the interference effects due to the multiple coupling points allow giant atoms to interact with each other through the waveguide without losing energy into the waveguide (theory in [2] and experiments in [3]).

This talk will review some of these developments [1-4]. Finally, we will also show how a giant atom coupled to a waveguide with varying impedance can give rise to chiral bound states [5].

[1] A.F. Kockum, Quantum optics with giant atoms -- the first five years, https://arxiv.org/abs/1912.13012

[2] A.F. Kockum, G. Johansson, F. Nori, Decoherence-Free Interaction between Giant Atoms in Waveguide Quantum Electrodynamics, Phys. Rev. Lett. 120, 140404 (2018). 

[3] B. Kannan, et al., Waveguide quantum electrodynamics with superconducting artificial giant atoms, Nature 583, pp. 775 (2020).

[4] S. Terradas-Brianso, et al., Ultrastrong waveguide QED with giant atoms, Phys. Rev. A 106, 063717 (2022). 

[5] X. Wang, T. Liu, A.F. Kockum, H.R. Li, F. Nori, Tunable Chiral Bound States with Giant Atoms, Phys. Rev. Lett. 126, 043602 (2021).

Traditional  approaches to quantum optics are rooted in the reciprocal, frequency-momentum space. In this talk, I will discuss recent advances toward sub-cycle quantum optics, where, instead, quantum fields are accessed in a localized region of space-time [1-2]. Both regimes will be compared side-by-side to contrast the advantages of each approach, with a particular emphasis on quantum sensing proposals [3-5] in the mid-infrared frequency range. In the concluding part of the talk, I will summarize recent advances in producing few-cycle bright one- and two-mode squeezed vacuum states in a single few-cycle spatio-temporal mode with macroscopic photon occupation [6]. Such capabilities are poised to unlock a new era of (extreme) nonlinear quantum optics in the attosecond regime [7].

[1] C. Riek et al.; Science 350, 420-423 (2015)

[2] I-C. Benea-Chelmus et al.; Nature 568, 202-206 (2019)

[3] S. Virally, P. Cusson, DVS; Phys. Rev. Lett. 127, 270504 (2021)

[4] S. Gündoğdu et al; Laser Phot. Rev. 17, 2200706 (2023)

[5] S. Onoe, S. Virally, DVS; arXiv:2307.13088 (2023)

[6] P. Cusson, S. Virally, DVS; IRMMW-THz Conference, paper Th-PM2-5-7 (2023)

[7] 2023 Nobel Prize in Physics: Pierre Agostini, Ferenc Krausz and Anne L'Huillier. Experimental methods that generate attosecond pulses for studying electron dynamics in matter. 

Approximate density functionals constructed to satisfy known mathematical properties of the exact density functional for the exchange-correlation energy of a many-electron system can be predictive over a wide range of materials and molecules. The strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation [1] satisfies 17 exact constraints, and nicely describes some systems that were formerly thought to be beyond the reach of density functional theory, such as the cuprates [2]. Ground states that break the symmetry of a Coulomb-interacting Hamiltonian can be understood as dynamic density or spin-density fluctuations that drop to low or zero frequency [3,4] and so persist over long times. In many cases, symmetry breaking transforms the strong correlation in a symmetry-unbroken wavefunction into moderate correlation like that found in the uniform electron gas of high or valence-electron density (an “appropriate norm” for constraint-based approximations).

Supported by NSF DMR-1939528 and DE-SC0018331

[1] J. Sun, A. Ruzsinszky, and J.P. Perdew, Phys. Rev. Lett. 115, 036402 (2015)

[2] J.W. Furness, Y. Zhang, C. Lane, I.G. Buda, B. Barbiellini, R.S. Markiewicz, A. Bansil, and J. Sun, Commun. Phys. 1, 11 (2018)

[3] P.W. Anderson, Science 177, 393 (1972)

[4] J.P. Perdew, A. Ruzsinszky, J. Sun, N.K. Nepal, and A.D. Kaplan, Proc. Nat. Acad. Sci. USA 118, e2017850118 (2021) 

Nuclear power plants, as history has shown, are capable of suffering severe accidents leading to the spread of radioactive contamination across large areas. This talk will explain why the possibility of future accidents can never be ruled out, focusing specifically on the case of fast neutron (breeder) reactors, a class of designs favoured by many people who propose these as the solution to the enduring problem of nuclear waste. It will combine insights from engineering and sociology to explain why nuclear energy is uniquely problematic. 

Collinear magnetic order characterized by zero net magnetization but finite polarization in the reciprocal space - spin texture - has recently been identified in several materials. These so called altermagnets share a number of technologically interesting features with ferromagnets, while retaining the advantages of antiferromagnets. The idea of excitonic condensation and excitonic insulator has been reappearing since the pioneering work of Mott in the early 1960's, most recently in the context of 2D materials revolution. I will discuss condensation of spinful excitons in the minimal, two orbital, Hubbard model. I will show that doping of the excitonic condensate away from integer filling leads to formation of collinear spin textures. Unlike the textures found in the known altermagnetic materials, the spin textures due to excitonic condensates may exists without ordered atomic moments or even without a finite spin density. The theory will be supported by numerical simulations using dynamical mean-field theory.