Weak value amplification for nonunitary evolution

Measuring small longitudinal phase shifts via weak measurement amplification

“…[8][9][10][11][12][13] Regardless of these arguments, the method of weak measurement has been shown powerful in solving quantum paradox, [14][15][16] reconstructing quantum state, [17][18][19][20] amplifying small effects [21][22][23][24][25] and investigat-ing foundations of the quantum world. [26][27][28][29][30][31] Among the above applications, weak value amplification (WVA) is particularly intriguing and has been rapidly developed in high-precision measurements. In order to realize WVA, the tiny quantity to be measured needs to be converted into the coupling coefficient of a von Neumann-type interaction Hamiltonian, which is small enough so that the condition of weak measurements is satisfied.…”

Amplifying single-photon nonlinearity using thermal light

“…[31] to revisit the von Neumann measurement with a meter wave function of the form of a plane wave. In a recent study, interferometric parameter estimation of the amplitude, instead of the phase is discussed based on imaginary weak value amplification [32], and the authors found that the amplitudemodulation weak amplification improve the precision of estimation and signal-to-noise ratio. Furthermore, we also show that imaginary weak amplification is a classical effect [33].…”

“…Recently, amplitude-modulation weak value amplification is also discussed in interferometric parameter estimation [32]. They find more Fisher information about the parameter can be recovered for the shifts in amplitude vary in a nonlinear way.…”