Related papers: High-harmonic and terahertz wave spectroscopy (HAT…
We study the linear- and nonlinear-optical lineshapes of metal nanoparticles (theory) and metallic photonic crystal slabs (experiment and theory). For metal nanoparticle ensembles, we show analytically and numerically that femtosecond…
We theoretically investigate photo-excitation of electron-hole pairs and high harmonic generation in the bulk of zinc oxide (ZnO) subjected to intense femto-second laser pulses with mid-infrared wavelength. The main microscopic mechanism of…
We report theoretical investigations of the tomographic procedure suggested by Itatani {\it et al.} [Nature, {\bf 432} 867 (2004)] for reconstructing highest occupied molecular orbitals (HOMO) using high-order harmonic generation (HHG).…
We present a comprehensive theoretical investigation of high-order harmonic generation in H$_2^+$ molecular ions within a quantum optical framework. Our study focuses on characterizing various quantum optical and quantum information…
We report attosecond-scale probing of the laser-induced dynamics in molecules. We apply the method of high-harmonic spectroscopy, where laser-driven recolliding electrons on various trajec- tories record the motion of their parent ion.…
Dynamical control of the nonlinear optical properties of solids -- with light itself -- will be essential for future ultrafast photonic technologies. Previously, methods to modulate nonlinear processes including second-harmonic generation…
The majority of sources of coherent optical radiation rely on laser oscillators driven by population inversion. Despite their technological importance in communications, medicine, industry, and other fields, it remains a challenge to access…
Terahertz waves hold immense potential across diverse fields, including healthcare monitoring, biomedical imaging, precision navigation, high-speed communication, security screening, industrial quality control, and space exploration.…
Coherent continuous wave (CW) terahertz spectroscopy is an extremely valuable technique that allows for the interrogation of systems that exhibit narrow resonances in the terahertz (THz) frequency range, such as high-quality (high-Q) THz…
Aims. Infrared (IR) spectroscopy is a powerful tool to study molecules in space. A key issue in such analyses is understanding the effect that temperature and anharmonicity have on different vibrational bands, and thus interpreting the IR…
High-order harmonic generation (HHG) in isolated atoms and molecules has been widely utilized in extreme ultraviolet (XUV) photonics and attosecond pulse metrology. Recently, HHG has also been observed in solids, which could lead to…
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…
We study strong field ionization of molecular hydrogen in highly intense co-rotating two-color (CoRTC) laser fields. The measured electron momentum distributions show alternating half-rings (AHR) that are characteristic for sub-cycle…
Experimental control and detection of atoms and molecules often rely on optical transitions between different electronic states. In many cases, substructure such as hyperfine or spin-rotation structure leads to the need for multiple optical…
Photomixing of two near-infrared lasers is well established for continuous-wave terahertz spectroscopy. Photomixing of three lasers allows us to measure at three terahertz frequencies simultaneously. Similar to Fourier spectroscopy, the…
Hyperspectral imaging is a technique that allows for the creation of multi-color images. At terahertz wavelengths, it has emerged as a prominent tool for a number of applications, ranging from non-ionizing cancer diagnosis and…
We illustrate an iterative method for retrieving the internuclear separations of N$_2$, O$_2$ and CO$_2$ molecules using the high-order harmonics generated from these molecules by intense infrared laser pulses. We show that accurate results…
We demonstrate to image asymmetric molecular orbitals via high-order harmonic generation in a one-color inhomogeneous field. Due to the broken inversion symmetry of the inhomogeneous field in space, the returning electrons with energy in a…
Although it seems that obtaining quantum properties of light from classical calculations is a self-contradictory claim, it is shown here that a unified mechanism governs the three distinct measurements of high harmonic generation spectra…
The selection rules of high harmonic generation (HHG) are investigated using three-dimensional time-dependent density functional theory (TDDFT). From the harmonic spectra obtained with various real molecules and different forms of laser…