Optics
New submissions
[ showing up to 2000 entries per page: fewer | more ]
New submissions for Fri, 17 May 24
- [1] arXiv:2405.09683 [pdf, ps, other]
-
Title: Plasmonic Nanocavity to Boost Single Photon Emission from Defects in Thin Hexagonal Boron NitrideAuthors: Mohammadjavad Dowran, Ufuk Kilic, Suvechhya Lamichhane, Adam Erickson, Joshua Barker, Mathias Schubert, Sy-Hwang Liou, Christos Argyropoulos, Abdelghani LaraouiSubjects: Optics (physics.optics); Quantum Physics (quant-ph)
Efficient and compact single photon emission platforms operating at room temperature with ultrafast speed and high brightness will be fundamental components of the emerging quantum communications and computing fields. However, so far, it has been very challenging to design practical deterministic single photon emitters based on nanoscale solid state materials that meet the fast emission rate and strong brightness demands. Here we provide a solution to this longstanding problem by using metallic nanocavities integrated with hexagonal boron nitride (hBN) flakes with defects acting as nanoscale single photon emitters (SPEs) at room temperature. The presented hybrid nanophotonic structure creates a rapid speedup and large enhancement in single photon emission at room temperature. Hence, the nonclassical light emission performance is substantially improved compared to plain hBN flakes and hBN on gold layered structures without nanocavity. Extensive theoretical calculations are also performed to accurately model the new hybrid nanophotonic system and prove that the incorporation of plasmonic nanocavity is key to the efficient SPE performance. The proposed quantum nanocavity single photon source is expected to be an element of paramount importance to the envisioned room temperature integrated quantum photonic networks.
- [2] arXiv:2405.09700 [pdf, ps, other]
-
Title: Unidirectional Amplification in the Frozen Mode Regime Enabled by a Nonlinear DefectComments: 4 pages, 3 figuresSubjects: Optics (physics.optics); Other Condensed Matter (cond-mat.other); Applied Physics (physics.app-ph)
A stationary inflection point (SIP) is a spectral singularity of the Bloch dispersion relation $\omega(k)$ of a periodic structure where the first and the second derivatives of $\omega$ with respect to $k$ vanish. An SIP is associated with a third order exceptional point degeneracy in the spectrum of the unit-cell transfer matrix, where there is a collapse of one propagating and two evanescent Bloch modes. At the SIP frequency, the incident wave can be efficiently converted into the frozen mode with greatly enhanced amplitude and vanishing group velocity. This can be very attractive for applications, including light amplification. Due to its non-resonant nature, the frozen mode regime (FMR) has fundamental advantages over common cavity resonances. Here, we propose a novel scheme for FMR-based unidirectional amplifiers by leveraging a tailored amplification/attenuation mechanism and a single nonlinear defect. The defect breaks the directional symmetry of the periodic structure and enables nonlinearity-related unidirectional amplification/ attenuation in the vicinity of the SIP frequency. We demonstrate the robustness of the amplification mechanism to local impurities and parasitic nonlinearity.
- [3] arXiv:2405.09758 [pdf, ps, other]
-
Title: Spatial-temporal manipulations of visible nanosecond sub-pulse sequences in an actively Q-switched Pr:YLF laserAuthors: Shengbo Xu, Yunru Chen, Ran Xia, Changcheng Duan, Qingrui Zeng, Yu Xiao, Xiahui Tang, Gang XuSubjects: Optics (physics.optics)
Pulsed visible lasers either by Q-switching or mode locking have been attracting intense attentions both in solid-state laser and fiber laser. Here, we report on the simultaneous manipulation of reconfigurable sub-pulse sequences and customizable high-order vortex beams in an actively Q-switched visible laser. On the one hand, pulse sequences with up to 4 sub-pulses could be generated and fully controlled by means of an acoustic-optic modulator driven by an arbitrary waveform generator. Both pulse number and pulse intensity can be manipulated through the programmable step-signal, which is also theoretically simulated through the rate equations. On the other hand, assisted by the off-axis pumping technique and the astigmatic mode conversion, the laser cavity could emit high-quality vortex beams carrying Laguerre-Gaussian modes up to 30th order. To the best of our knowledge, this is the most flexible active manipulations not only on the intensity distribution of the transverse modes but also on the temporal distribution of the pulse sequences in a visible laser. The versatile manipulating techniques in this work could be immediately implemented into all other solid-state lasers to obtain sub-pulse vortex beams, which may provide enhanced functionality and flexibility for a large range of laser systems.
- [4] arXiv:2405.09844 [pdf, ps, other]
-
Title: Electrically switchable $2^N$-channel wave-front control with N cascaded polarization-dependent metasurfacesAuthors: Zhiyao Ma, Tian Tian, Yuxuan Liao, Xue Feng, Yongzhuo Li, Kaiyu Cui, Fang Liu, Hao Sun, Wei Zhang, Yidong HuangSubjects: Optics (physics.optics); Applied Physics (physics.app-ph)
To increase the operating channels of polarization-dependent metasurfaces, we proposed a structure of $N$ cascaded dual-channel metasurfaces to achieve $2^N$ electrically switchable functional channels without intrinsic noise or cross-talk. As proof of principles, we have implemented a 3-layer setup to achieve 8 switchable channels. In success, we have demonstrated two typical applications of vortex beam generation with switchable topological charge of l=-3 ~ +4 or l=-1~ -8, and beam steering with the deflecting direction switchable in an 8*1 line or a 4*2 grid. We believe that our proposal would provide a practical way to extend the functionality of polarization-multiplexed metasurfaces, which are potential for the applications of LiDAR, glasses-free 3D display, OAM (de)multiplexing, and varifocal meta-lens.
- [5] arXiv:2405.10038 [pdf, ps, other]
-
Title: Silicon nitride integrated photonics from visible to mid-infrared spectraAuthors: Kirill A. Buzaverov (1 and 2), Aleksandr S. Baburin (1 and 2), Evgeny V. Sergeev (1), Sergey S. Avdeev (1), Evgeniy S. Lotkov (1), Sergey V. Bukatin (1), Ilya A. Stepanov (1), Aleksey B. Kramarenko (1), Ali Sh. Amiraslanov (1), Danil V. Kushnev (1), Ilya A. Ryzhikov (1 and 3), Ilya A. Rodionov (1 and 2) ((1) FMN Laboratory, Bauman Moscow State Technical University, Moscow, Russia, (2) Dukhov Research Institute of Automatics (VNIIA), Moscow, Russia, (3) Institute for Theoretical and Applied Electromagnetics Russia Academy of Science, Moscow, Russia)Comments: 62 pages, 20 figuresSubjects: Optics (physics.optics); Applied Physics (physics.app-ph)
Recently, silicon nitride (Si3N4) photonic integrated circuits (PICs) are of a great interest due to their extremely low waveguides losses. The number of Si3N4 integrated photonics platform applications is constantly growing including the Internet of Things (IoT), artificial intelligence (AI), light detection and ranging (LiDAR) devices, hybrid neuromorphic and quantum computing. Their heterogeneous integration with a III-V platform leads to a new advanced large scale PICs with thousands of elements. Here, we review key trends in Si3N4 integrated circuits technology and fill an information gap in the field of state-of-the-art photonic devices operating from visible to mid-infrared spectra. A comprehensive overview of Si3N4 integrared circtuis microfabrication process details (deposition, lithography, etching, etc.) is introduced. Finally, we point out the limits and challenges of silicon nitride photonics performance in an ultrawide range providing routes and prospects for their future scaling and optimization.
- [6] arXiv:2405.10104 [pdf, ps, other]
-
Title: On-chip integrated metasystem for spin-dependent multi-channel colour holographyComments: 18 pages and 11 figuresSubjects: Optics (physics.optics); Applied Physics (physics.app-ph)
On-chip integrated metasurface driven by in-plane guided waves is of great interests in various light field manipulation applications such as colorful augmented reality and holographic display. However, it remains a challenge to design colorful multichannel holography by a single on-chip metasurface. Here we present metasurfaces integrated on top of guided-wave photonic slab that achieves multi-channel colorful holographic light display. An end-to-end scheme is used to inverse design the metasurface for projecting off-chip preset multiple patterns. Particular examples are presented for customized patterns that were encoded into the metasurface with a single-cell meta-atom, working simultaneously at RGB color channels and for several different diffractive distance, with polarization dependence. Holographic images are generated at 18 independent channels with such a single-cell metasurface. The proposed design scheme is easy to implement and the resulting device is viable to fabrication, promising a plenty of applications in nanophotonics.
- [7] arXiv:2405.10109 [pdf, ps, other]
-
Title: In-situ optical vector analysis based on integrated lithium niobate single-sideband modulatorsAuthors: Hanke Feng, Tong Ge, Yaowen Hu, Zhenzheng Wang, Yiwen Zhang, Zhaoxi Chen, Ke Zhang, Wenzhao Sun, Cheng WangSubjects: Optics (physics.optics); Applied Physics (physics.app-ph)
Optical vector analysis (OVA) is an enabling technology for comprehensively characterizing both amplitude and phase responses of optical devices or systems. Conventional OVA technologies are mostly based on discrete optoelectronic components, leading to unsatisfactory system sizes, complexity, and stability. They also encounter challenges in revealing the on-chip characteristics of integrated photonic devices, which are often overwhelmed by the substantial coupling loss and extra spectral response at chip facets. In this work, we demonstrate a miniaturized OVA system for integrated photonics devices based on broadband single sideband (SSB) modulators on a thin-film lithium niobate (LN) platform. The OVA could provide a direct probe of both amplitude and phase responses of photonic devices with kHz-level resolution and tens of terahertz measurement bandwidth. We perform in-situ characterizations of single and coupled microring resonators fabricated on the same chip as the OVA, unfolding their intrinsic loss and coupling states unambiguously. Furthermore, we achieve the direct measurement of collective phase dynamics and density of states of the Bloch modes in a synthetic frequency crystal, by in-situ OVA of a dynamically modulated microring resonator. Our in-situ OVA system provides a compact, high-precision, and broadband solution for characterizing future integrated photonic devices and circuits, with potential applications ranging from optical communications, biosensing, neuromorphic computing, to quantum information processing.
- [8] arXiv:2405.10118 [pdf, other]
-
Title: Beyond memory-effect matrix-based imaging in scattering media by acousto-optic gatingSubjects: Optics (physics.optics); Applied Physics (physics.app-ph)
Imaging inside scattering media at optical resolution is a longstanding challenge affecting multiple fields, from bio-medicine to astronomy. In recent years, several groundbreaking techniques for imaging inside scattering media, in particular scattering-matrix based approaches, have shown great promise, but usually suffer from a restricted field of view (FOV) due to their reliance on the optical 'memory-effect'. Here, we demonstrate that by combining acousto-optic spatial-gating with state-of-the-art matrix-based imaging techniques, diffraction-limited imaging beyond the optical memory-effect can be achieved in a robust fashion. Specifically, we show that this can be achieved by computational processing of scattered light fields captured under scanned acousto-optic modulation. The approach can be directly utilized whenever the ultrasound focus size is of the order of the memory-effect range, independently of the scattering angle.
- [9] arXiv:2405.10163 [pdf, ps, other]
-
Title: Electrically Injected mid-infrared GeSn laser on Si operating at 140 KAuthors: Sudip Acharya, Hryhorii Stanchu, Rajesh Kumar, Solomon Ojo, Mourad Benamara, Guo-En Chang, Baohua Li, Wei Du, Shui-Qing YuSubjects: Optics (physics.optics); Applied Physics (physics.app-ph)
Owing to its true direct bandgap and tunable bandgap energies,GeSn alloys are increasingly attractive as gain media for mid-IR lasers that can be monolithically integrated on Si. Demonstrations of optically pumped GeSn laser at room under pulsed condition and at cryogenic temperature under continuous-wave excitation show great promise of GeSn lasers to be efficient electrically injected light sources on Si. Here we report electrically injected GeSn lasers using Fabry-Perot cavity with 20, 40, and 80 micron ridge widths. A maximum operating temperature of 140 K with lasing threshold of 0.756 kA/cm2 at 77 K and emitting wavelength of 2722 nm at 140 K was obtained. The lower threshold current density compared to previous works was achieved by reducing optical loss and improving the optical confinement. The peak power was measured as 2.2 mW/facet at 77 K.
- [10] arXiv:2405.10173 [pdf, ps, other]
-
Title: Asymmetric Transmission through Polarization-Controlled Riemann Surface Evolution PathSubjects: Optics (physics.optics)
Exceptional points (EPs) are degeneracies at which two or more eigenvalues and eigenstates of a non-Hermtian system coalesce. Dynamically encircling EPs leads to chiral mode switching, where the final state of the system depends on the encircling handedness. In conventional schemes, the encircling direction is the same for different polarization states of the same mode, resulting in the same chiral transmission. Here, by mapping evolution path onto a double couple L-shaped silicon waveguide, we demonstrate opposite evolution directions for modes with different polarizations, thus achieving opposite asymmetric transmission results. Our work shows that the polarization state of the input mode can also serve as a variable parameter influencing the evolution path on the Riemann surfaces.
- [11] arXiv:2405.10203 [pdf, other]
-
Title: Fast Gain Dynamics in Interband Cascade LasersAuthors: Florian Pilat, Andreas Windischhofer, Maximilian Beiser, Vito F. Pecile, Elizaveta Gangrskaia, Audrius Pugžlys, Robert Weih, Johannes Koeth, Andrius Baltuška, Oliver H. Heckl, Benedikt SchwarzSubjects: Optics (physics.optics)
Interband Cascade Lasers (ICL) have matured into a versatile technological platform in the mid-infrared spectral domain. To broaden their applicability even further, ongoing research pursues the emission of ultrashort pulses. The most promising approach is passive mode-locking with a fast saturable absorber. However, despite vast attempts no passive mode-locked ICL has been demonstrated up to date. In this study we perform pump-probe measurements on the ICL gain and show that its dynamics are mainly ($\sim$70%) governed by a fast recovery time of 2 ps. Our findings explain why passive mode-locking has not succeeded so far, shedding a new light on ICL dynamics as we propose strategies to overcome the current limitations.
Cross-lists for Fri, 17 May 24
- [12] arXiv:2405.09571 (cross-list from eess.SP) [pdf, other]
-
Title: The Best Radar Ranging Pulse to Resolve Two ReflectorsComments: 8 pages, 8 figuresSubjects: Signal Processing (eess.SP); Data Analysis, Statistics and Probability (physics.data-an); Optics (physics.optics); Quantum Physics (quant-ph)
Previous work established fundamental bounds on subwavelength resolution for the radar range resolution problem, called superradar [Phys. Rev. Appl. 20, 064046 (2023)]. In this work, we identify the optimal waveforms for distinguishing the range resolution between two reflectors of identical strength. We discuss both the unnormalized optimal waveform as well as the best square-integrable pulse, and their variants. Using orthogonal function theory, we give an explicit algorithm to optimize the wave pulse in finite time to have the best performance. We also explore range resolution estimation with unnormalized waveforms with multi-parameter methods to also independently estimate loss and time of arrival. These results are consistent with the earlier single parameter approach of range resolution only and give deeper insight into the ranging estimation problem. Experimental results are presented using radio pulse reflections inside coaxial cables, showing robust range resolution smaller than a tenth of the inverse bandedge, with uncertainties close to the derived Cram\'er-Rao bound.
- [13] arXiv:2405.09690 (cross-list from cond-mat.mtrl-sci) [pdf, ps, other]
-
Title: The appeal of small molecules for practical nonlinear opticsAuthors: Ivan BiaggioComments: 11 pages, 5 figuresJournal-ref: Chem. Eur. J., 28, e202103168 (2022)Subjects: Materials Science (cond-mat.mtrl-sci); Optics (physics.optics)
Small organic molecules with a {\pi}-conjugated system that consists of only a few double or triple bonds can have significantly smaller optical excitation energies when equipped with donor- and acceptor groups, which raises the quantum limits to the molecular polarizabilities. As a consequence, third-order nonlinear optical polarizabilities become orders of magnitude larger than those of molecules of similar size without donor-acceptor substitution. This enables strong third-order nonlinear optical effects (as high as 1000 times those of silica glass) in dense, amorphous monolithic assemblies. These properties, accompanied by the possibility of deposition from the vapor phase and of electric-field poling at higher temperatures, make the resulting materials competitive towards adding an active nonlinear optical or electro-optic functionality to state-of-the-art integrated photonics platforms.
- [14] arXiv:2405.09808 (cross-list from quant-ph) [pdf, other]
-
Title: Phase Retrieval from the Hong-Ou-Mandel Dip to Characterize the Phase Spectrum of Independent Pulses at the Single-Photon LevelSubjects: Quantum Physics (quant-ph); Optics (physics.optics)
Measuring the phase spectrum at the single-photon level is essential for the full characterization of the temporal-spectral mode of quantum sources. We present a phase retrieval algorithm-based method to recover the phase spectrum difference between two independent pulses from their Hong-Ou-Mandel interference pattern and intensity spectra. Our confirmatory experiment with coherent state pulses confirms the accuracy of the recovered phase spectrum difference to within plus or minus 0.1 rad. The method we employ is readily generalizable to the measurement of single-photon wave packets and even correlated photon pairs.
- [15] arXiv:2405.09845 (cross-list from quant-ph) [pdf, ps, other]
-
Title: Nanomechanically induced transparency in $\mathcal{PT}$-symmetric optical cavitiesComments: 7 pages, 6 figuresSubjects: Quantum Physics (quant-ph); Optics (physics.optics)
In this paper, we analytically present the phenomena of nanomechanically induced transparency (NMIT) and transmission rate in a parity-time-symmetric ($\mathcal{PT}$-symmetric) opto-nanomechanical system (ONMS) where a levitated dielectric nanospheres is trapped near the antinodes closest to right mirror of passive cavity which further coupled to an active cavity via hoping factor. We find that the phenomenon of NMIT may be generated from the output probe field in the presence of an effective opto-nanomechanical coupling between the cavity field and the nanosphere, whose steady-state position is influenced by the Coulomb interaction between the cavity mirror and the nanosphere. In addition, the width and height of the transparency window can be controlled through the effective optomechanical coupling, which is readily adjusted by altering changing the nanosphere's radius and the Coulomb interaction. One of the most interesting result is the transition NMIT behavior in $\mathcal{PT}$-symmetric and broken $\mathcal{PT}$-symmetric regime. We show that the presence of nanosphere in the passive cavity enhances the width and transmission rate of NMIT window in passive-passive regime and in passive-active regime, a notable decrease of sideband amplification has been observed. These results show that our scheme may find some potential applications for optical signal processing an and quantum information processing.
- [16] arXiv:2405.10154 (cross-list from quant-ph) [pdf, ps, other]
-
Title: Quantum CZ Gate based on Single Gradient MetasurfaceSubjects: Quantum Physics (quant-ph); Optics (physics.optics)
We propose a scheme to realize quantum controlled-Z (CZ) gates through single gradient metasurface. Using its unique parallel beam-splitting feature, i.e., a series of connected beam splitters with the same splitting ratio, one metasurface can support a CZ gate, several independent CZ gates, or a cascaded CZ gates. Taking advantage of the input polarization determined output path-locking feature, both polarization-encoded and path-encoded CZ gates can be demonstrated on the same metasurface, which further improves the integration level of quantum devices. Our research paves the way for integrating quantum logical function through the metasurface.
- [17] arXiv:2405.10279 (cross-list from quant-ph) [pdf, ps, other]
-
Title: Photon emission from macroscopic currentsAuthors: Rainer DickSubjects: Quantum Physics (quant-ph); Optics (physics.optics)
Coherent states are a well-established tool of quantum optics to describe electromagnetic waves in terms of photons. However, they do not describe the near-field regime of radiation sources. Instead, we generically use classical solutions of Maxwell's equations to describe radiation in the near-field regime. The classical solutions provide linear relations between currents and emitted electromagnetic fields, whereas evolution of states at the quantum level proceeds through unitary time evolution operators involving photon operators. This begs questions how the classical radiation equations relate to unitary quantum evolution, and how we can describe macroscopic fields from antennas or magnetic coils in terms of elementary photons. The present paper answers both questions through the construction of generalized Glauber states for radiation emitters.
Replacements for Fri, 17 May 24
- [18] arXiv:2401.02733 (replaced) [pdf, ps, other]
- [19] arXiv:2403.04174 (replaced) [pdf, other]
-
Title: Investigation of nanophotonic lithium niobate waveguides for on-chip evanescent wave sensingComments: 9 pages, 3 figures (main text); 6 pages, 5 figures (supplemental). Submitted to Optics ExpressSubjects: Optics (physics.optics); Applied Physics (physics.app-ph)
- [20] arXiv:2404.06873 (replaced) [pdf, other]
-
Title: Aluminium nanoparticle-based ultra-wideband high-performance polarizerSubjects: Optics (physics.optics); Applied Physics (physics.app-ph); Computational Physics (physics.comp-ph)
- [21] arXiv:2405.06810 (replaced) [pdf, ps, other]
-
Title: Simulating Light Propagation through Biological Media Using Monte-Carlo MethodAuthors: Maryam GhahremaniComments: arXiv admin note: text overlap with arXiv:1711.03244 by other authorsSubjects: Optics (physics.optics); Biological Physics (physics.bio-ph)
- [22] arXiv:2403.01583 (replaced) [pdf, other]
-
Title: Universal spectral moment theorem and its applications in non-Hermitian systemsComments: 8 Pages, 4 FiguresSubjects: Mesoscale and Nanoscale Physics (cond-mat.mes-hall); Quantum Gases (cond-mat.quant-gas); Optics (physics.optics)
- [23] arXiv:2405.08157 (replaced) [pdf, other]
-
Title: Towards a fiber-optic temporally multiplexed single photon sourceAuthors: Agustina G. Magnoni, Laura T. Knoll, Lina Wölcken, Julián Defant, Julián Morales, Miguel A. LarotondaComments: 6 pages, 6 figuresSubjects: Quantum Physics (quant-ph); Optics (physics.optics)
[ showing up to 2000 entries per page: fewer | more ]
Disable MathJax (What is MathJax?)
Links to: arXiv, form interface, find, physics, recent, 2405, contact, help (Access key information)