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Hybrid lead halide perovskites, such as methylammonium lead halides CH3NH3PbX3 (MAPbX3, X = I, Br, Cl), are emerging as an excellent class of materials for various optoelectronic applications including solar cells, light-emitting diodes, lasers, and photodetectors [1,2]. As for these perovskite-based devices, deep understanding of transport properties of excitons and charge carriers in perovskite...
We report the new method for the measurement of the phase-relaxation time T2 of a medium with femtosecond time resolution. The method is based on the effect of quantum interference of entangled photons and does not require the actual use of a femtosecond light source. The method provides the practical and cost-efficient alternative to existing methods of ultrafast time-resolved spectroscopy [1].
In aperiodically poled quasi-phase-matching (QPM) crystals, parametric down-conversion (PDC) can generate very broadband pulsed squeezed light. This is because each part of the crystal will generate squeezed light at a different frequency [1]. But the emission will be thus inhomogeneously broadened, and one requires special measures to eliminate the chirp accompanying the pulses. This can be done...
Quantum state engineering has seen important developments over the last decade. The use of hybrid protocols, combining the discrete and continuous variables of light, can achieve high detection efficiencies, making them a good candidate for the production of non-classical states. Schrödinger cat states (SCSs), superpositions of two coherent states |α〉 in phase opposition (ψcat) 〉 |α〉 ± |-α〉), constitute...
Novel nonlinear optical crystals have attracted considerable interests due to their wide applications in frequency shifting, terahertz generation, optical communications, display, sensing, and so on. Because terahertz radiation is sensitive to free carriers and lattice vibrations in solid states, terahertz time-domain spectroscopy (THz-TDS) has become a pivotal tool in investigating fundamental dynamics...
Nonlinear image up-conversion is an alternative for the acquisition of real-time and full unscanned 2D images at different spectral ranges of the infrared [1, 2] where sensors are not fully developed, as compared to existing imaging sensors in the visible in terms of noise, speed, resolution, or uncooled operation. Wavelength shift is accomplished through a sum-frequency mixing (SFM) process in a...
Upconversion detection is a promising technology for measurement of IR signals in the 1.5 μm–2 μm region used for lidar remote sensing [1-2]. In comparison to conventional InGaAs detector, the upconversion detector can achieve IR detection with better signal-to-noise ratio (SNR), not only due to lower dark noise directly, but also because of its limited field-of-view and acceptance bandwidth that...
Stimulated Raman scattering presents one of important trends in nonlinear optics enabling to generate Stokes-shifted radiation at frequencies that are not readily available from solid state lasers. This method is suitable also because the phase matching fulfilment isn't required. To get stable and efficient Raman generation of picosecond and even femtosecond ultra-short Stokes pulses, the method of...
Detection of chemical species using differential absorption lidar is a topic of growing interest for safety in petrochemical facilities, outdoor air quality measurements, greenhouse gases monitoring from space, and standoff detection of toxic chemical plumes. In such a lidar the optical source must combine a high energy (> 10 mJ for range-resolved detection), a wide and arbitrary wavelength tunability,...
Many trivalent rare earth ions, such as praseodymium (Pr), samarium (Sm), terbium (Tb) and dysprosium (Dy), have radiative transitions in the visible wavelength region, and those visible lasers have been reported [1]. Especially, Pr3+-doped lasers are successful so far as one of the most efficient approaches for visible lasing thanks to the development of indium gallium nitride (InGaN) diode lasers.
Lead halide perovskite semiconductors have recently gained interest for their application in a wide range of different optoelectronic devices, demonstrating impressive performances in solid-state photovoltaic devices [1] with impressive efficiencies exceeding 20% and great potential for lighting and lasing application [2,3]. These materials not only show exceptional primary optoelectronic properties...
Manipulation of perovskite crystallinity in order to obtain the desired optoelectronic properties is a critical issue. Perovskite structural characterization has been carried out applying several tools, which usually interrogate bulky portions of the material, averaging out over the inhomogeneities at the sub-micron scale [1]. Preliminary results obtained through photoluminescence microscopy across...
Parametric downconversion (PDC) allows the generation of highly coherent, spectrally pure single photons for quantum photonics. In a typical heralded PDC source, the signal photon emerges in a spectrally mixed state due to strong (anti)correlation in the joint spectrum of PDC photon pairs.
Optical vortex or orbital angular momentum (OAM) of light are a subject of active research and have been employed for novel applications such as optical manipulation, quantum information and control of cold atoms [1]. For decades, it has been discussed if OAM of light could affect the state of a bound system of charges such as an atom or a molecule, an exchange should arise between light and matter,...
Up to this point, photon-entanglement sources suffered from the compromise of being either compact or efficient, but not both at the same time [1-6]. Our new concept of creating entanglement [7] combines most of the advantages of the various existing schemes. The setup offers high coupling efficiencies due to its collinear design and is still as compact and simplistic as a BBO source [1], requiring...
Squeezed states of light are referred to as non-classical field states and are known to be characterized by strong correlations between photons both in the spectral and spatial domain. For these reasons they are very perspective for many important and interesting practical applications in modern quantum optics including storage and transfer of quantum information. From this point of view multiphoton...
Femtosecond pulses are primarily generated at 800 or 1030 nm in Tiisapphire or Yb based systems. To generate fully tunable pulses over the full visible and NIR range, optical parametric amplifiers and in particular white light seeded noncollinear optical parametric amplifiers (NOPA) are now widely used. For highest energy pulses this scheme is expanded to OPCPAs. Energy and beam pointing stability...
The precise characterization of femtosecond laser pulses is as challenging as their generation and a topic of intense research. Dispersion-scan (d-scan) [1] is a recently established technique where the spectrum of a nonlinear signal, e.g., second-harmonic generation (SHG), is measured as a function of dispersion applied to the pulse. The spectral phase of the pulse can then be retrieved from the...
Promising potential of several novel ternary crystals (TI4YXS3, Y=Sn, Pb; X=S, Te) for applications in infrared (IR) optoelectronics, LEDs (light emitting diodes) and photodetectors operating in the middle and far IR spectral ranges has been demonstrated in the present work. Besides, these materials can be used as thermoelectric materials [1], IR harmonic frequency triggers, modulators, optical memory...
The remarkable progress in nonlinear materials and laser pump sources continues to advance optical parametric oscillators (OPOs) to new frontiers in spectral and temporal coverage and performance capability, with no end in sight. The advent of a new class of mid-infrared (mid-IR) birefringent nonlinear materials such as CdSiP2 (CSP) and quasi-phase-matched (QPM) crystals such as orientation-patterned...
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