Quantum state truncation using an optical parametric amplifier and a beam splitter

Nonclassicalities of hybrid coherent states

“…We also found that small SPAC state components can significantly change the HC states' quantumness. The non-classical properties of the HC states may be tuned by varying the superposition parameter ε, which depends on the amplifier strength [63] and the beam-splitter transmittance [33,38,60,65,76].…”

“…Over the last decades, various schemes to generate and optimize several quantum states, including Fock states [1][2][3], Schrödinger cat states [4][5][6][7][8][9][10][11][12][13][14], squeezed states [15], photon number states [16][17][18][19][20][21][22], binomial states [23][24][25], and squeezed state excitations [26][27][28][29] have been proposed and implemented. Furthermore, it has been shown that adding or subtracting photons can change the physical properties of a given state [30], and thus effective methods for generating photon-added or subtracted states have been realized using conditional measurements on a beam splitter [31][32][33]. The photon-added coherent states [34][35][36], photonsubtracted or -added squeezed states [37][38][39] have attracted interest due to their potential applications in several protocols for quantum information processing [40].…”

“…In these schemes, the initial coherent state component appears naturally at the output in case of 'negative postselection'. However, one may wonder whether the superposition of SPAC and coherent states may be obtained and exploited [33,35,[60][61][62][63][64].…”

Enhancing nonclassical properties of quantum states of light using linear optics

“…An essential requirement for leveraging such technologies is the preparation of states of light having nonclassical properties like quadrature squeezing or sub-Poissonian statistics. Several quantum state engineering protocols can be found in the literature, involving the interaction of light in special media [2,3], or in cavity QED systems [4,5], as well as schemes of photon addition [6][7][8], photon subtraction [9], the use of arrays of beam splitters followed by photodetections [10], quantum state truncation ("quantum scissors") [11][12][13], and Fock state filtering ("hole burning") [14][15][16]. Those methods can provide a large variety of quantum states of light but often require nonclassical resources, e.g., the previous generation of single-photon states [11].…”

Entanglement and output squeezing in a distant nano-electro-optomechanical system generated by optical parametric amplifiers

“…In addition, the lightmechanical entanglement in a cavity optomechanical system involving OPA exhibits manifestation of classical nonlinear dynamics [11]. As is well known, OPA nonlinearity leads to many interesting quantum phenomena [12][13][14][15]. Such as electromagnetically induced transparency, photon antibunching and quantum limits.…”