Experimental Preparation and Manipulation of Squeezed Cat States via an All‐Optical In‐Line Squeezer

Abstract

The squeezed cat state, an essential quantum resource, can be used for quantum error correction and slowing decoherence of the optical cat state. However, preparing a squeezed cat state with high generation rate, and effectively manipulating it, remain challenging. In this work, a high-performance all-optical in-line squeezer is developed to prepare a squeezed cat state and manipulate the phase of the quadrature squeezing. This scheme has the advantages that the phase of the quadrature squeezing of the squeezed cat state can be manipulated by changing the working condition of the squeezer, and that a higher generation rate can be achieved via the deterministic squeezing operation of the in-line squeezer. The generation rate of squeezed cat states reaches 2 kHz, the same as that of the initial cat state. The all-optical in-line squeezer proposed here removes the requirements of electro-optic and opto-electric conversions necessary for an off-line squeezer, thus enabling high-bandwidth squeezing operations on non-Gaussian states. These results provide an efficient method to prepare and manipulate optical squeezed cat states, which makes a step closer to their applications in all-optical quantum information processing.

Generating superpositions of quantum states via a beam splitter with position measurement

“…In addition, the squeezed quantum state can also achieve the possibility of reducing the noise of a quantum signal below the vacuum limit [60,61]. Therefore, squeezed states have many practical applications in quantum optics and quantum information [62,63]. To investigate squeezing effects in the output state in equation (17), some novel squeezing properties are expected to be found.…”

Simultaneous Preparation of Two Optical Cat States Based on a Nondegenerate Optical Parametric Amplifier

“…[4][5][6][7][8][9][10] It has been experimentally prepared in different systems, such as cavity atomic system, [11,12] ion trap, [13] superconducting quantum circuits, [14][15][16] and optical system. [17][18][19][20][21][22][23] The optical cat state, which is defined as the superposition of two coherent states with opposite phases, can be prepared by subtracting photons from a squeezed vacuum state [17][18][19][20][21][22][23] and with dissipatively coupled degenerate optical parametric oscillators. [24,25] It is an important quantum resource for quantum communication, [21] quantum computation, [4,5,26,27] and quantum metrology.…”

“…[35] An approximate odd cat state is heralded if a photon is subtracted from the squeezed vacuum state. [17][18][19][21][22][23] However, such a scheme costs two optical cavities. The nondegenerate optical parametric amplifier (NOPA), on the other hand, enables one to prepare two squeezed states simultaneously from one optical cavity instead of two.…”