The resolutions of the optical lithography is limited by the well-known Rayleigh limit. Although the atom lithography can generate features smaller than this limit, the spacing of the pattern is still limited by the optical wavelength. Here, we proposed two atom lithography methods, both of which used the coherent Rabi oscillation to break the diffraction limit. One is in the microwave regime where the Rydberg atom is used and micrometer resolution can be achieved. The other is in the optical regime where sub-10 nanometer resolution is possible.
Quantum entanglement is a critical resource for quantum information and quantum computation. However, entanglement of a quantum system is subjected to change due to the interaction with the environment. One typical result of the interaction is the amplitude damping that usually results in the reduction of the entanglement. Here we propose a protocol to protect quantum entanglement from the amplitude damping by applying Hadamard and CNOT gates. As opposed to some recently studied methods, the scheme presented here does not require weak measurement in the reversal process, leading to a faster recovery of entanglement. We propose a possible experimental implementation based on linear optical system.
The resolutions of the optical microscope and the optical lithography are both limited by the well-known Rayleigh
limit. Rabi oscillation is a coherent nonlinear process that can modulate the population distribution between
two energy states and also modulate the resonant fluorescence spectrum. If we have a gradient electric field
amplitude in the space, the Rabi frequency for different position is also different. The spatial distribution of the
population in the excited state can be modulated and the spatial information of the atoms can also be encoded
in the resonant fluorescence spectrum. If the gradient of the field is large enough, the pattern generated can be
subwavlength and the atoms with subwavelength distances can also be extracted. Here we present a review on
both the subwavelength photolithography and microscopy via Rabi oscillations.