Generation of a continuous-wave squeezed vacuum state at 1.3 μm by employing a home-made all-solid-state laser as pump source

Abstract

We present a continuous-wave squeezed vacuum generation system at a telecommunication wavelength of 1.3 μm. By employing a home-made single-frequency Nd:YVO4 laser with dual wavelength outputs as the pump source, via an optical parameter oscillator based on periodically poled KTP, a squeezed vacuum of 6.1 dB±0.1 dB below the shot noise limit at 1342 nm is experimentally measured. This system could be utilized for demonstrating practical quantum information networks.

A low-noise, high-SNR balanced homodyne detector for the bright squeezed state measurement in 1–100 kHz range*

“…The increase of the capacitance C 1 is benefit to obtaining lower cut-off frequency at the AC branch. [21] However, large capacitance C 1 can also introduce excess electronic noise. In this case, the capacitance C 1 of 47 µF is selected.…”

“…[6][7][8][9][10] While the bright squeezed state has a coherent amplitude, which can be used in spectroscopic measurement, [11,12] velocimetry, [13] LIDAR, [14] and quantum key distribution. [15,16] The detection, [17,18] besides the generation [19][20][21][22] and propagation of squeezed states, is another key element for improving their application performances. Many dedicated researches have been carried out to explore a balanced homodyne detector (BHD) with low-noise, high-gain, and high common mode rejection ratio (CMRR).…”

Optical Crystals for 1.3 μm All-Solid-State Passively Q-Switched Laser

“…Hence, the 1.3 µm laser radar can output greater power and realize remote eye-safe detection. In addition, due to the low loss and low dispersion characteristics of the 1.3 µm wavelength in the fiber, it has been widely used in the fields of communication and biosensing, for example, in the generation of non-classical optical field [1], spectral detection [2], and remote sensing [3]. Further, the 1.3 µm wavelength laser can be used as a light source to obtain a variety of wavelength lasers through nonlinear changes such as frequency doubling [4], frequency quadrupling [5], sum frequency generation [6], and Raman scattering [7].…”

A compact Einstein–Podolsky–Rosen entangled light source

“…[13] In 1992, the CV EPR entangled light was first generated experimentally by Ou et al with a non-degenerate optical parametric amplifier (NOPA) operating below the oscillation threshold. [14] Subsequently, scientists around the world experimentally obtained the EPR entangled light with various wavelengths, [14][15][16][17][18][19][20] which were desirable to enhance the correlations of amplitude or/and phase quadrature. So far, CV entangled states with high entanglement degrees over 10 dB [20] and multipartite CV entangled states used for quantum networks [3,21,22] have been realized experimentally.…”