Related papers: Shaping terahertz harmonic frequency combs with fr…
The intense terahertz (THz) pulses facilitate the observation of various nonlinear optical effects and manipulation of material properties. In this work, we report a convenient approach that can produce strong broadband terahertz pulses…
Chip-based terahertz (THz) devices are emerging as versatile tools for manipulating mm-wave frequencies in the context of integrated high-speed communication technologies for potential sixth-generation (6G) wireless applications. The…
High-field terahertz (THz) pulse generation is investigated through the interaction of an intense single-color CO2 laser pulse with helium (He) gas targets. Employing multi-dimensional Particle-In-Cell (PIC) simulations, this study reveals…
High-order nonlinear light-matter interactions in gases enable generation of x-ray and attosecond light pulses, metrology, and spectroscopy. Optical nonlinearities in solid-state materials are particularly interesting for combining optical…
Frequency combs are powerful tools for many applications and high performances are achieved by stabilizing these lasers. For operation in the mid-infrared, quantum cascade lasers (QCL) are ideal candidates as they present numerous…
Active frequency comb generation and waveform control are central challenges in the terahertz (THz) domain. In THz quantum cascade lasers (QCLs), these functions have typically been achieved through active bias modulation, which alters the…
With their incomparable time-frequency accuracy, frequency combs have significantly advanced precision spectroscopy, ultra-sensitive detection, and atomic clocks. Traditional methods to create photonic, phononic, and magnonic frequency…
Recently developed techniques for generating precisely equidistant optical frequencies over broad wavelength ranges are revolutionizing precision physical measurement [1-3]. These frequency "combs" are produced primarily using relatively…
The quantum cascade laser (QCL) has evolved to be a compact, powerful source of coherent mid-infrared (mid-IR) light. However, its fast gain dynamics strongly restricts the formation of ultrashort pulses. As such, the shortest pulses…
High energy single- to few-cycle terahertz pulses enable the exploration of the frontier of science, such as electron acceleration, strong-field physics, and spectroscopy. One important method of generating such terahertz pulses is to use…
This paper proposes a method for generating phononic frequency combs (PFCs) using defect-localized modes in a two-dimensional hexagonal phononic crystal. Localized vibration modes from a singular point defect produce evenly spaced spectral…
Quantum cascade lasers (QCL) have revolutionized the generation of mid-infrared light. Yet, the ultrafast carrier transport in mid-infrared QCLs has so far constituted a seemingly insurmountable obstacle for the formation of ultrashort…
Gas-filled hollow-core fiber (HCF) pulse post-compressors generating few- to single-cycle pulses are a key enabling tool for attosecond science and ultrafast spectroscopy. Achieving optimum performance in this regime can be extremely…
We present an experimental study of optical frequency comb generation based on cascaded quadratic nonlinearities inside a continuous-wave-pumped optical parametric oscillator. We demonstrate comb states which produce narrow-linewidth…
Dual terahertz (THz) comb spectroscopy is a promising methods for high accuracy, high resolution, and broadband THz spectroscopy because the mode-resolved THz comb spectrum possesses both characteristics of broadband THz radiation and…
A laser pulse composed of a fundamental and an appropriately phased second harmonic can drive a time-dependent current of photoionized electrons that generates broadband THz radiation. Over the propagation distances relevant to many…
Frequency combs based on terahertz quantum cascade lasers feature broadband coverage and high output powers in a compact package, making them an attractive option for broadband spectroscopy. Here, we demonstrate the first multi-heterodyne…
Terahertz (THz) frequency combs are increasingly essential for spectroscopy, metrology, and quantum science. However, generating a dense array of evenly spaced ultra-narrow THz comb lines is challenging. Here, we demonstrate broadband THz…
A general mechanism for the generation of frequency combs referenced to atomic resonances is put forward. The mechanism is based on the periodic phase control of a quantum system's dipole response. We develop an analytic description of the…
A theoretical analysis is carried out for the recently developed three-pulse photon echo spectroscopy employing dual frequency combs (DFC) as the light sources. In this method, the molecular sample interacts with three pulse trains derived…