arXiv subjects

Michał Mikołajczyk

Publications and source records attributed to Michał Mikołajczyk.

5 recordsLinked to original sources

arXiv2026

Observation of Photon Bunching in Broadband Multimode Thermal Light Enabled by Temporal Imaging

Photons emitted by incoherent sources exhibit temporal bunching, a fundamental manifestation of Bose-Einstein statistics first observed by Hanbury Brown and Twiss (HBT). While intensity correlation measurements originated in astronomy and are now central across quantum technologies, biophysics, and spectroscopy, observing temporal bunching in broadband thermal light remains limited by detector temporal resolution. Conventional approaches - such as streak cameras or optical upconversion - introduce severe trade-offs in efficiency, bandwidth, or setup versatility. Here, we propose and demonstrate a third route: pre-detection temporal magnification of the optical field prior to measuring its intensity autocorrelation function in a conventional HBT setup. Using an electro-optic time lens with a temporal magnification of 660, we resolve the temporal intensity autocorrelation of broadband thermal light generated via non-degenerate spontaneous parametric down-conversion with a bandwidth of 250 GHz. This enables direct observation of thermal photon bunching on sub-3.5 picosecond timescales without narrow spectral filtering, establishing pre-detection temporal imaging as a general platform for broadband statistical optics, with applications spanning ultrafast quantum optics, biophysical imaging, and potentially stellar intensity interferometry.

physics.optics↗

arXiv2024

Interfacing picosecond and nanosecond quantum light pulses

Light is a key information carrier, enabling worldwide high-speed data transmission through a telecommunication fibre network. This information-carrying capacity can be extended to transmitting quantum information (QI) by encoding it in single photons -- flying qubits. However, various QI-processing platforms operate at vastly different timescales. QI-processing units in atomic media, operating within nanosecond to microsecond timescales, and high-speed quantum communication, at picosecond timescales, cannot be efficiently linked due to orders of magnitude mismatch in the timescales or, correspondingly, spectral linewidths. In this work, we develop a large-aperture time lens using complex high-bandwidth electro-optic phase modulation to bridge this gap. We demonstrate coherent, deterministic spectral bandwidth compression of quantum light pulses by more than two orders of magnitude with high efficiency. It will facilitate large-scale hybrid QI-processing by linking the ultrafast and quasi-continuous-wave experimental platforms, which until now, to a large extent, have been developing independently.

quant-ph↗

arXiv2022

Electro-optic Fourier transform chronometry of pulsed quantum light

The power spectrum of an optical field can be acquired without a spectrally resolving detector by means of Fourier-transform spectrometry, based on measuring the temporal autocorrelation of the optical field. Analogously, we here perform temporal envelope measurements of ultrashort optical pulses without time resolved detection. We introduce the technique of Fourier transform chronometry, where the temporal envelope is acquired by measuring the frequency autocorrelation of the optical field in a linear interferometer. We apply our technique, which is the time-frequency conjugate measurement to Fourier-transform spectrometry, to experimentally measure the pulse envelope of classical and single photon light pulses.

physics.optics↗

arXiv2020

Aperiodic electro-optic time lens for spectral manipulation of single-photon pulses

Electro-optic time lenses are promising experimental components for photonic spectral-temporal processing of quantum information. We report a stable method to realize an electro-optic time lens, which relies on the amplification of an electronic response of a fast photodiode. The method does not require a repetitive clock and may be applied to aperiodic optical signals. We experimentally demonstrate the approach using single-photon pulses and directly verify its aperiodicity. The approach will enable construction of complex electro-optic temporal optical systems.

physics.optics↗

arXiv2016

Efficient adaptation of complex-valued noiselet sensing matrices for compressed single-pixel imaging

Minimal mutual coherence of discrete noiselets and Haar wavelets makes this pair of bases an essential choice for the measurement and compression matrices in compressed-sensing-based single-pixel detectors. In this paper we propose an efficient way of using complex-valued and non-binary noiselet functions for object sampling in single-pixel cameras with binary spatial light modulators and incoherent illumination. The proposed method allows to determine m complex noiselet coefficients from m+1 binary sampling measurements. Further, we introduce a modification to the complex fast noiselet transform, which enables computationally-efficient real-time generation of the binary noiselet-based patterns using efficient integer calculations on bundled patterns. The proposed method is verified experimentally with a single-pixel camera system using a binary spatial light modulator.

cs.CV↗