I consider quantized electromagnetic field as physical system for the implementation of continuous variable quantum information processing tasks.
Quantized electromagnetic field
The classical electromagnetic field is described as a collection of modes, which are solutions to the Maxwell equations and upon quantization, each mode behaves like a quantum harmonic oscillator.
The quadrature amplitudes are the relevant degrees of freedom of the quantized electromagnetic field, which are mathematically equivalent to the position and momentum variables of the harmonic oscillator.
In CV QIP, different state and processes can be braodly divided in two categories: Gaussian and non-Gaussian
Since optical Kerr nonlinearity are weak, we resort to photon number detection for the generation of non-Gaussian states.
Schematic for the implementation of (a) photon subtraction, (b) photon addition, and (c) photon catalysis on a single mode system.
I intend to undertake various studies involving non-Gaussian states. These include engineering of non-Gaussian states, their characterization and their advantages in various QIP protocols such as quantum teleportation and quantum metrology. I also want to study the effects of dissipation and inefficient detectors on the performance of these quantum protocols. I also aim to provide ways to lessen the effects of dissipation.
Schematic of quantum teleportation: To begin with, an entangled resource is shared between Alice and Bob namely TMSV state. An unknown input quantum state to be teleported is provided to Alice. She combines her mode and the single-mode input state using a balanced beam splitter. After that, the two output modes of the beam splitter are subjected to homodyne measurement by her, and the results are classically communicated to Bob. Based on the results, he displaces his mode, and the state of the resultant mode corresponds to the teleported state.