Related papers: Conclusive nonlinear phase sensitivity limit for a…
After reviewing parity measurement based interferometry with twin-Fock states, which allows for super-sensitivity (Heisenberg-limited) and super-resolution, we consider interferometry with two different superpositions of twin-Fock states,…
The standard quantum limit (SQL), also known as the shot-noise limit, defines how quantum fluctuations of light constrain measurement precision. In a benchmark experiment using the Mach-Zehnder interferometer (MZI), where a coherent state…
When a photon interferes with itself while traversing a Mach-Zehnder inteferometer, the output port where it emerges is influenced by the phase difference between the interferometer arms. This allows for highly precise estimation of the…
We propose a theoretical scheme to enhance the phase sensitivity by introducing a Kerr nonlinear phase shift into the traditional SU(1,1) interferometer with a coherent state input and homodyne detection. We investigate the realistic…
A beam splitter is an important component of an atomic/optical Mach-Zehnder interferometer. Here we study a Bose Einstein Condensate beam splitter, realized with a double well potential of tunable height. We analyze how the sensitivity of a…
We investigate the phase sensitivity of a linear two-mode atom interferometer subject to environmental noise, modeled within the framework of open quantum systems with both number-conserving and non-conserving Lindblad operators.…
The sensitivity properties of an SU(1,1) interferometer made of two cascaded parametric amplifiers, as well as of an ordinary SU(2) interferometer preceded by a squeezer and followed by an anti-squeezer, are theoretically investigated.…
It is commonly maintained that entanglement is necessary to beat the shot noise limit in the sensitivity with which certain parameters can be measured in interferometric experiments. Here we show that, with a fluctuating number of two-mode…
We theoretically studied the quantum Cram\'{e}r-Rao bound of an actively correlated Mach-Zehnder interferometer (ACMZI), where the quantum Fisher information obtained by the phase-averaging method can give the proper phase-sensing limit…
A number of authors have suggested that nonlinear interactions can enhance resolution of phase shifts beyond the usual Heisenberg scaling of 1/n, where n is a measure of resources such as the number of subsystems of the probe state or the…
We present a theoretical investigation of a whispering gallery mode (WGM) resonator coupled to a Mach-Zehnder interferometer (MZI) and show a bimodal coincidence transmission spectrum when the input state is an indistinguishable photon…
The Heisenberg limit traditionally provides a lower bound on the phase uncertainty scaling as 1/<N>, where <N> is the mean number of photons in the probe. However, this limit has a number of loopholes which potentially might be exploited,…
Quantum Cramer-Rao (QCR) bound is attached to a particular nonclassical state, therefore appropriate choice of the probe state is of the key importance to enhance sensitivity beyond classical one. Since the work of C.M. Caves (Phys. Rev. D…
In two-mode interferometry, for a given total photon number $N$, entangled Fock state superpositions of the form $(|N-m\rangle_a|m\rangle_b+e^{i (N-2m)\phi}|m\rangle_a|N-m\rangle_b)/\sqrt{2}$ have been considered for phase estimation.…
We experimentally demonstrate stable and user-adjustable single-photon interference in a 1 km long fiber- optical Mach-Zehnder interferometer, using an active phase control system with the feedback provided by a classical laser. We are able…
We study the phase sensitivity of SU(2) and SU(1,1) interferometers fed by two-mode field states which are intelligent states for Hermitian generators of the SU(2) and SU(1,1) groups, respectively. Intelligent states minimize uncertainty…
When measuring a time-varying phase, the standard quantum limit and Heisenberg limit as usually defined, for a constant phase, do not apply. If the phase has Gaussian statistics and a power-law spectrum $1/|\omega|^p$ with $p>1$, then the…
It has been suggested that both quantum superpositions and nonlinear interactions are important resources for quantum metrology. However, to date the different roles that these two resources play in the precision enhancement are not well…
The super-sensitivity attained in quantum phase estimation is known to be compromised in the presence of decoherence. This is particularly patent at blind spots -- phase values at which sensitivity is totally lost. One remedy is to use a…
Interferometry with NOON quantum states can provide unbiased phase estimation with a sensitivity scaling as $\Delta \theta \sim 1/N_T$ given a prior knowledge that the true phase shift $\theta$ lies in the interval $-\pi \leq \theta \leq…