arXiv subjects

Kritika Jain

Publications and source records attributed to Kritika Jain.

5 recordsLinked to original sources

arXiv2024

Strong Dipole-Dipole Interactions via Enhanced Light-Matter Coupling in Composite Nanofiber Waveguides

We study the interaction of emitters with a composite waveguide formed from two parallel optical nanofibers in currently unexplored regimes of experimental importance for atomic gases or solid-state emitters. Using the exact dyadic Green's function we comprehensively investigate the coupling efficiency and the fiber-induced Lamb shift accounting for variations in emitter positions and fiber configurations. This reveals coupling efficiencies and Purcell factors that are enhanced considerably beyond those using a single fiber waveguide, and robustness in the figures of merit. We finally investigate resonant dipole-dipole interactions and the generation of entanglement between two emitters mediated through the composite waveguide under excitation. We show that the concurrence can be enhanced for two fiber systems, such that entanglement may be present even in cases where it is zero for a single fiber. All-fiber systems are simple in construction and benefit from a wealth of existing telecommunications technologies, whilst enjoying strong couplings to emitters and offering novel light-matter functionalities specific to slot waveguides.

quant-ph↗

arXiv2022

Radiative decay of an emitter due to non-Markovian interactions with dissipating matter

It is known that the more tractable Markovian models of coupling suited for weak interactions may overestimate the Rabi frequency notably when applied to the strong-coupling regime. Here, a more significant consequence of the non-Markovian interaction between a photon emitter and dissipating matter such as resonant plasmonic nanoparticles is described. A large increase of radiative decay and a diminished non-radiative loss is shown, which unravels the origin of unexpected large enhancements of surface-enhanced-Raman-spectroscopy (SERS), as well as the anomalous enhancements of emission due to extremely small fully absorbing metal nanoparticles less than 10 nm in dimensions. We construct the mixture of pure states of the coupled emitter-nanoparticle system, unlike conventional methods that rely on the orthogonal modes of the nanoparticle alone.

physics.optics↗

arXiv2022

Role of Rabi oscillations in radiative states due to the fully absorbing smaller plasmonic nanoparticles

The modified radiative and non-radiative states due to the weak coupling of an emitter with other resonant objects (Purcell effect), can be recast as a quantum interference of the paths of the photon that define the classical scattering and absorption by the object. When the coupling is stronger, additional paths representing the (Rabi oscillations or) possible re-absorption of the photon from the excited object, by the emitter at ground-state, have to be included in the quantum interference. The effect of these additional Rabi paths of the photon on the radiative states and the efficiency of spontaneous emission, can be approximated using a simple one-loop correction to the weak-coupling approximation. This effect is especially evident in the anomalous enhancements of emission due to extremely small non-scattering (or fully absorbing) metal nanoparticles less than 10 nm in dimensions. Extending these corrections to a collective model of spontaneous emission that includes multiple emitters and such very small metal nanoparticles coupled to each other, the large contribution of Rabi paths to radiative decay in such bulk materials is elucidated.

physics.optics↗

arXiv2018

Emitter-Vacuum coupling through a leaky nanostructure and the role of dynamics in density of optical states

We show a break down of the conventional partition of optical states into its radiative and non-radiative parts. Large divergence of experimental observations from current theory in the case of emitters interacting with fully absorbing plasmonic nanoparticles only a few nanometers in dimensions, are now evident. A model of fluctuation-dissipation demands non-local behavior from limiting small metal nanoparticles and proximal metal surfaces. We point that widely used techniques to enhance optical sensing such as surface-enhanced-Raman-spectroscopy (SERS), may not have been viable but for this effect. Qualitatively, this quantum effect seems to present itself only when the classical probability of scattering of an emitted photon by a near-by absorbing nanostructure approaches zero. Hence, though different in origin and scale, this has an interesting analogy with quantum effects resulting in Hawking radiation near a black-hole.

cond-mat.mes-hall↗

arXiv2015

Can JSP Code be Generated Using XML Tags?

Over the years, a variety of web services have started using server-side scripting to deliver results back to a client as a paid or free service; one such server-side scripting language is Java Server Pages (JSP). Also Extensible markup language (XML), is being adopted by most web developers as a tool to describe data.Therefore, we present a conversion method which uses predefined XML tags as input and generates the corresponding JSP code. However, the end users are required to have a basic experience with web pages. This conversion method aims to reduce the time and effort spent by the user (web developer) to get acquainted with JSP. The conversion process abstracts the user from the intricacies of JSP and enables him to focus on the business logic.

cs.OH↗