Wide-field SU(1,1) interferometer

Abstract

An SU(1, 1) interferometer uses a sequence of two optical parametric amplifiers for achieving subshot-noise sensitivity to a phase shift introduced in between. We present the first realization of a wide-field SU(1, 1) interferometer, where the use of a focusing element enables spatially multimode operation within a broad angle. Over this angle, the interference phase is found to be flat. This property is important for the high sensitivity to the phase front disturbance. Further, −4.3 ± 0.7 dB quadrature squeezing, an essential requirement to the high sensitivity, is experimentally demonstrated for plane-wave modes inside the interferometer. Such an interferometer is useful not only for quantum metrology, but also in remote sensing, enhanced sub-shot-noise imaging, and quantum information processing.Interferometers have been used for more than a century to measure physical quantities with high accuracy. Recently, the experimental realization of SU(1, 1) interferometers has raised significant interest due to the loss-tolerant sub-shot-noise sensitivity [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The core idea is to use a series of two optical parametric amplifiers (OPAs) to probe phase shifts between them [15,16]. Possible applications are in remote sensing [11] and in quantum information processing [14], but such a scheme is especially attractive for quantum metrology with optical [2,7,9], atom [5,17] and hybrid [18] interferometers.The two-mode squeezed state employed in an SU(1, 1) interferometer is a quantum resource that helps to overcome the Letter Vol. X, No. X / April 2016 / Optica 4

Video‐Rate Imaging with Undetected Photons

“…The crystal is placed in a Michelson‐type interferometer as shown in Figure . [ 32–35 ]…”

“…The crystal is placed in a Michelson-type interferometer as shown in Figure 1. [32][33][34][35] In our setup, signal and idler beams have different wavelengths. While the idler beam is used to illuminate the object the signal beam is detected with an EMCCD or with a CMOS camera.…”

Hyperspectral infrared microscopy with visible light

“…With this demonstration, a new hyperspectral IR microscopy will be unlocked for practical applications in bioimaging and material analysis. We should also mention the possibility of implementing the method in high gain (43) or stimulated (44,45) regimes of PDC, which is an exciting topic for further investigations.…”

Spectrally multimode integrated SU(1,1) interferometer

“…Indeed, PDC sources generate photon pairs with finite spectral and spatial bandwidths and generally in more than a single mode. Therefore, the complete description of SU(1,1) interferometers should account for the presence of such spatial [29,30,31] and spectral modes [32,33,34] in order to correctly engineer the system [35] and accordingly maximize the phase sensitivity [36].…”