Nano-mechanical Systems

Quantum Optics of Nanomechanical Oscillator Near The Instability Point

Another upcoming area with many new exciting results concerns the existence of quantum effects at macroscopic level. Creating and manipulating quantum states in a macroscopic mechanical system would address issues, such as the physics of decoherence, that are of fundamental importance. There are also potential applications to quantum computing and communication, quantum-limited displacement, force, and mass sensing. From a scientific perspective, nanomechanical oscillators are the leading candidates in a current worldwide effort to observe quantum behavior. The previous works mostly concerned variety of methods and techniques in the stable linear regime of the oscillator. In line with the work in quantum optics on squeezing, one can consider studying the squeezed states of the nanomechanical oscillator. There are proposals that consider producing squeezing by modulating the spring constant. Here in this work, I analyzed the situation in the new regime near to the Euler buckling instability point where the nonlinearity effects take place. By numerically solving the Schrodinger equation, I showed the existence of amplitude squeezing in Nanomechanical oscillator having an externally controlled Euler buckling nonlinearity. Although the observation would be experimentally challenging, what makes me very interested in this problem is that the prospect of exploring tunable quantum squeezing in nanomechanical oscillators and the connection to the Euler buckling instability are intriguing. In future, I am planning to work on this problem in more detail. One interesting investigation can be to couple the nanomechanical oscillator with its externally controlled nonlinearity to a two level Cooper-pair box system. The detection of the Cooper-pair box in special states would give rise to a variety of states of the mechanical oscillator such as a combination of cat states and squeezed states.