arXiv subjects

Jarosław Sotor

Publications and source records attributed to Jarosław Sotor.

9 recordsLinked to original sources

arXiv2026

Shot-noise-limited few-cycle mid-infrared frequency comb with attosecond phase stability

Achieving sub-cycle waveform control with attosecond-level precision while reaching shot-noise-limited amplitude stability in the mid-infrared spectral range remains a central challenge for ultrafast and precision optical science. Here, we demonstrate a fully stabilized, ultra-stable optical frequency comb (OFC) based on a Kerr-lens mode-locked Cr:ZnS laser operating at 2.3 $μ$m. The oscillator delivers 40 fs pulses at a 25 MHz repetition rate, which are spectrally broadened to cover two octaves and compressed to a 1.4-cycle, 11 fs duration. Pumped by a custom low-noise erbium-doped fiber amplifier, the laser exhibits an integrated relative intensity noise (RIN) of 0.0026% over 10 Hz--1 MHz, while the noise of the few-cycle output is further suppressed to 0.0017% and reaches the shot-noise limit for Fourier frequencies above 5 kHz. It represents the lowest amplitude noise reported to date for any mode-locked laser. This unprecedented amplitude stability enables carrier-envelope phase (CEP) stabilization with a residual integrated phase noise of only 1.5 mrad (10 Hz--12.5 MHz), corresponding to a CEP jitter of 1.8 as, the highest phase stability for any laser system ever reported. The long-term performance of the fully stabilized OFC is measured over 24 hours, with a power stability of 0.01% and a residual CEP noise of 17 mrad. By combining few-cycle mid-infrared pulses with shot-noise-limited intensity noise and attosecond-level phase stability, the reported OFC provides access to new regimes of quantum-limited metrology and control of ultrafast light-matter interactions.

physics.optics↗

arXiv2026

Incoherent Fourier transform spectroscopy with room-temperature coverage from NIR to THz

Despite the broadband nature of thermal light sources, optical spectroscopy over multiple spectral bands simultaneously remains challenging. Here, we demonstrate a practical Fourier transform infrared spectrometer (FTIR) that achieves room-temperature spectral coverage from 1 to 50 $μ$m (300--6 THz) in seconds using a single set of optics, with the long wave cutoff extendable to 90 $μ$m (3.3 THz) and the short wave to the ultraviolet (0.39 $μ$m). The interferometer employs a diamond plate beam splitter and windowless lithium tantalate (LTO) detector to probe the spectrum of combined incoherent sources operating at different temperatures. Applications of the instrument in modern chemometry, material science, and medicine are envisioned.

physics.optics↗

arXiv2026

Infrared photonics for healthcare: A roadmap for proactive and predictive health management

The field of infrared (IR) photonics is currently undergoing remarkable progress, moving rapidly towards practical sensing applications demanded by medical therapy and diagnostics (theranostics). The Developments can be divided into three main categories: (i) novel devices and measurement concepts including advanced updates of classical approaches that push medical sensing into the spotlight; (ii) new demonstrations of photonic integrated circuit (PIC-)based IR devices enabling highly miniaturized sensors for point-of-care application as well as medical and wellness wearables; and (iii) technologically-mature IR demonstrators that enable first medical sensing and treatment applications. This roadmap paper provides a consolidated overview of this highly dynamic and interdisciplinary research field with a focus on the major roadblocks that limit the widespread adoption of IR photonics in large-scale medical diagnostics. Special attention is given to the ambivalence between the molecular-level spectroscopic interpretation and a broader health-state assessment, highlighting the need for a common framework. Additionally, the paper discusses the critical importance of unified measurement standards, calibration protocols, and medical certification processes to ensure the validity of experimental results, reproducibility, and clinical trust, particularly when novel experimental techniques and AI algorithms are involved. Perspectives from major past and current contributors to application-oriented IR photonics will be provided.

physics.app-ph↗

arXiv2024

Ultra-broadband room-temperature Fourier transform spectrometer with watt-level power consumption

Fourier-transform infrared spectroscopy (FTIR) has matured into a versatile technique with relevance for environmental monitoring, pharmaceutical research, and food safety applications. However, compared to other spectroscopic methods, it experiences slower progress in terms of power optimization, miniaturization, and adoption by industry. To overcome this limitation, we developed an ultra-broadband room-temperature FTIR instrument relying on commercially available components that offers a spectral coverage from 1.6 $μ$m to 31 $μ$m (9.7-190 THz) without changing optics at a single-Watt-level of electrical power consumption. To demonstrate the capabilities of the instrument, we measured atmospheric species in multiple spectral regions with better than 1.5 cm$^{-1}$ resolution.

physics.ins-det↗

arXiv2024

Dual-dispersion-regime dual-comb mode-locked laser

We report on the first solid-state dual-comb mode-locked laser simultaneously operating in different dispersion regimes. Due to the intrinsic polarization-multiplexing in a birefringent Yb:Ca$_3$NbGa$_3$Si$_2$O$_{14}$ (Yb:CNGS) gain medium, the laser emits two cross-polarized pulse trains with a repetition rate offset of ~4.8 kHz from a single cavity. We obtain dual pulse generation with 20-fold difference in the duration, by setting the net cavity group delay dispersion to cross zero across the emission band of the employed gain medium. While the duration of the soliton-like pulses experiencing anomalous dispersion amounts to 117 fs, the second laser output that is spectrally located in the normal dispersion region, is strongly chirped with a pulse duration of 2360 fs.

physics.optics↗

arXiv2022

Soliton trapping and orthogonal Raman scattering in a birefringent microstructured fiber

We report on trapped pulse generation in birefringent microstructured optical fiber. Linearly polarized fs pulses are injected into the microstructured fiber in anomalous dispersion regime. We observed experimentally that soliton pulse polarized along the fast fiber axis partially transfers its energy to the orthogonal polarization. The generated pulse is amplified through the orthogonal Raman gain. The two polarization components are located at group-velocity matched wavelengths. The experimental works are supported with numerical simulations. The obtained results are important for the light sources using self-frequency shifted solitons in applications demanding high polarization purity.

physics.optics↗

arXiv2020

Dual-comb femtosecond solid-state laser with inherent polarization-multiplexing

Dual-comb spectroscopy is a rapidly developing technique enabling ultraprecise broadband optical diagnostics of atoms and molecules. This powerful tool typically requires two phase-locked femtosecond lasers, yet it has been shown that it can be realized without any stabilization if the combs are generated from a single laser cavity. Still, unavoidable intrinsic relative phase-fluctuations always set a limit on the precision of any spectroscopic measurements, hitherto limiting the applicability of bulk dual-comb lasers for mode-resolved studies. Here, we demonstrate a versatile concept for low-noise dual-comb generation from a single-cavity femtosecond solid-state laser based on intrinsic polarization-multiplexing inside an optically anisotropic gain crystal. Due to intracavity spatial separation of the orthogonally-polarized beams, two sub-100 fs pulse trains are simultaneously generated from a 1.05 $μ$m Yb:CNGS oscillator with a repetition rate difference of 4.7 kHz. The laser exhibits the lowest relative noise ever demonstrated for a bulk dual-comb source, supporting free-running mode-resolved spectroscopic measurements over a second. Moreover, the developed dual-comb generation technique can be applied to any solid-state laser exploiting a birefringent active crystal, paving the way towards a new class of highly-coherent, single-cavity, dual-comb laser sources operating in various spectral regions.

physics.optics↗

arXiv2020

Compact mode-locked Er-doped fiber laser for broadband cavity-enhanced spectroscopy

We report the design and characteristics of a simple and compact mode-locked Er-doped fiber laser and its application to broadband cavity-enhanced spectroscopy. The graphene mode-locked polarization maintaining oscillator is thermally stabilized and equipped with three actuators that control the repetition rate: fast and slow fiber stretchers, and metal-coated fiber section. This allows wide tuning of the repetition rate and its stabilization to an external reference source. The applicability of the laser to molecular spectroscopy is demonstrated by detecting CO2 in air using continuous-filtering Vernier spectroscopy.

physics.optics↗

arXiv2019

Computational Doppler-limited dual-comb spectroscopy with a free-running all-fiber laser

Dual-comb spectroscopy has emerged as an indispensable analytical technique in applications that require high resolution and broadband coverage within short acquisition times. Its experimental realization, however, remains hampered by intricate experimental setups with large power consumption. Here, we demonstrate an ultra-simple free-running dual-comb spectrometer realized in a single all-fiber cavity suitable for the most demanding Doppler-limited measurements. Our dual-comb laser utilizes just a few basic fiber components, allows to tailor the repetition rate difference, and requires only 350 mW of electrical power for sustained operation over a dozen of hours. As a demonstration, we measure low-pressure hydrogen cyanide within 1.7 THz bandwidth, and obtain better than 1% precision over a terahertz in 200 ms enabled by a drastically simplified all-computational phase correction algorithm. The combination of the unprecedented setup simplicity, comb tooth resolution and high spectroscopic precision paves the way for proliferation of frequency comb spectroscopy even outside the laboratory.

physics.ins-det↗