Weak localization of photon noise

Abstract

We present an experimental study of coherent backscattering (CBS) of photon noise from multiple scattering media. We use a pseudothermal light source with a microsecond coherence time to produce a noise spectrum covering a continuous transition, from wave fluctuations to shot noise over several MHz. The angle-dependent Fano factor of backscattered light shows an enhancement due to CBS in the wave fluctuation regime. The CBS line shape and enhancement factor of the noise power is consistent with theory in the weak-scattering limit and for a large number of open reflection channels. These initial experiments on weakly scattering media demonstrate that sensitive noise measurements can be combined with the separation of path lengths present in CBS, opening up new experiments on noise transport in the localization regime. Contents

Focus on quantum efficiency

“…Whereas most networks within the random ensemble give rise to destructive interference on the output node-and thus rather low transport efficiency-the opposite is true for specific (and on average more symmetric, see [2]) configurations leading to constructive interference. These findings agree with the following general picture of coherent wave transport in random media [17]: coherence reduces transport on average, due to enhanced backscattering [10,20,21] and disorder-induced localization (e.g. Anderson localization [13,22]), whereas, at the same time, fluctuations around the average are increased [23], thus admitting the existence of specific disorder realizations with exceptionally high transfer efficiency.…”

Second order interference of chaotic light reflected from random medium

“…Note that resent experiments Ref. [11] were performed in the regime of large coherence length compared to the size of the system.…”

“…Interestingly, the reflection of light from multiple scattering medium on average is an angle independent and has a weak localization peak due to the constructive interference of light in the backscattering direction. It is a precursor manifestation of Anderson localization Pioneering work on weak localization of photon noise have been reported recently [11]. It was found weak localization narrow peak in backscattering of photon noise.…”

Statistical distribution of quantum correlation induced by multiple scattering in the disordered medium

“…The studies of the multiple scattering for quantized lights in a disordered medium have received long-sustained attentions [1][2][3][4][5][6][7][8][9][10][11], which leads to a bunch of novel phenomena in the quantum optics theory, such as, the quantum noise transmitted through a multiple scattering medium [12,13], the identification of frequency [14] and spatial [15][16][17] quantum correlations (QCs), among the others. Besides, this quantum optical system, nonclassical lights illuminating on a disordered medium, has a great potential for numerous applications in quantum information processing, including programmable quantum optical circuit [18][19][20], Heisenberglimit resolution imaging [21,22], quantum optical authentication [23][24][25][26], and quantum communication [27].…”