collaborators

5 papers

quant-ph2026

Gain-induced spectral non-degeneracy in type-II parametric down-conversion

Behnood Taheri, Denis Kopylov, Manfred Hammer +3

We demonstrate the novel effect of gain-induced spectral shifts in the type-II parametric down-conversion (PDC) process, which results in a transition from degenerate to non-degene…

quant-ph2025

Bipartite entanglement extracted from multimode squeezed light generated in lossy waveguides

Denis A. Kopylov, Torsten Meier, Polina R. Sharapova

Entangled two-mode Gaussian states constitute an important building block for continuous variable quantum computing and communication protocols. In this work, we theoretically stud…

quant-ph2025

Multiphoton, multimode state classification for nonlinear optical circuits

Denis A. Kopylov, Christian Offen, Laura Ares +5

We introduce a new classification of multimode states with a fixed number of photons. This classification is based on the factorizability of homogeneous multivariate polynomials an…

quant-ph2025

Theory of Multimode Squeezed Light Generation in Lossy Media

Denis A. Kopylov, Torsten Meier, Polina R. Sharapova

A unified theoretical approach to describe the properties of multimode squeezed light generated in a lossy medium is presented. This approach is valid for Markovian environments an…

quant-ph2025

Spectral and temporal properties of type-II parametric down-conversion: The impact of losses during state generation

Denis A. Kopylov, Michael Stefszky, Torsten Meier +2

In this paper, we theoretically study spectral and temporal properties of pulsed spontaneous parametric down-conversion (SPDC) generated in lossy waveguides. Our theoretical approa…