arXiv subjects

Manas Mukherjee

Publications and source records attributed to Manas Mukherjee.

23 records · Page 2Linked to original sources

arXiv2016

Optical Barium Ion Qubit

We demonstrate an optical single qubit based on 6S1/2 to 5D5/2 quadrupole transition of a single Ba+ ion operated by diode based lasers only. The resonance wavelength of the 6S1/2 to 5D5/2 quadrupole transition is about 1762 nm which suitably falls close to the U-band of the telecommunication wavelength. Thus this qubit is a naturally attractive choice towards implementation of quantum repeater or quantum networks using existing telecommunication networks. We observe continuous bit-flip oscillations at a rate of about 250 kHz which is fast enough for the qubit operation as compared to the measured coherence time of over 3 ms. We also present a technique to quantify the bit-flip error in each qubit NOT gate operation.

physics.atom-ph↗

arXiv2015

Tuning energy transport using interacting vibrational modes

We study energy transport in a chain of quantum harmonic and anharmonic oscillators where the anharmonicity is induced by interaction between local vibrational states of the chain. Using adiabatic elimination and numerical simulations with matrix product states, we show how strong interactions significantly slow down the relaxation dynamics (with the emergence of a new time scale) and can alter the properties of the steady state. We also show that steady state properties are completely different depending on the order in which the limits of infinite time and infinite interaction are taken.

cond-mat.quant-gas↗

arXiv2014

Signature of Non-Abelian to Abelian Transition in Spin Systems Through Geometric Phase

Abelian and Non-Abelian evolution of a quantum system manifests differently in the geometric phase acquired by the system under such evolutions. In this work we develop and study, using dressed state techniques, an experimentally realizable spin system which allows us to transit smoothly from non-Abelian to Abelian evolutions by changing externally controllable parameters. The study provides insights into the underlying physical phenomenon governing such a transition allowing us greater control on phase generation in a quantum system. The robustness of geometric phase against fluctuations of the external parameters of the system has also been studied in this work. The noise analysis has direct consequence on the present search for fault tolerant quantum gates using geometric phase.

quant-ph↗

arXiv2014

SeD Radical: A probe for measurement of time variation of Fine Structure Constant($α$) and Proton to Electron Mass Ratio($μ$)

Based on the spectroscopic constants derived from highly accurate potential energy surfaces, the SeD radical is identified as a spectroscopic probe for measuring spatial and temporal variation of fundamental physical constants such as the fine-structure constant (denoted as $α=\frac{e^2}{\hbar c}$) and the proton-to-electron mass ratio (denoted as $μ=\frac{m_p}{m_e}$). The ground state of SeD ($X^2Π$), due to spin-orbit coupling, splits into two fine structure multiplets $^2Π_{\frac{3}{2}}$ and $^2Π_{\frac{1}{2}}$. The potential energy surfaces of these spin-orbit components are derived from a state of the art electronic structure method, MRCI+Q inclusive of scalar relativistic effects with the spin-orbit effects accounted through the Breit-Pauli operator. The relevant spectroscopic data are evaluated using Murrel-Sorbie fit to the potential energy surfaces. The spin-orbit splitting($ω_f$) between the two multiplets is similar in magnitude with the harmonic frequency ($ω_e$) of the diatomic molecule. The amplification factor derived from this theoretical method for this particular molecule can be as large as 350, on the lower side it can be about 34. The significantly large values of K indicate that SeD radical can be a plaussible experimental candidate for measuring variation in $α$ and $μ$.

physics.atom-ph↗

arXiv2006

Photon correlation vs interference of single-atom fluorescence in a half-cavity

Photon correlations are investigated for a single laser-excited ion trapped in front of a mirror. Varying the relative distance between the ion and the mirror, photon correlation statistics can be tuned smoothly from an antibunching minimum to a bunching-like maximum. Our analysis concerns the non-Markovian regime of the ion-mirror interaction and reveals the field establishment in a half-cavity interferometer.

quant-ph↗