Related papers: Non-degenerate 2-photon excitation in scattering m…
Entangled two-photon absorption can enable a linear scaling of fluorescence emission with the excitation power. In comparison to classical two-photon absorption with a quadratic scaling, this can allow fluorescence imaging or…
Two-photon fluorescence imaging has shown a promising application in biomedical imaging due to its outstanding advantages such as large penetration depth, low photo-damage, and photo-bleaching, etc. Among them, the two-photon fluorescent…
The epitaxial growth of two-dimensional (2D) $\beta-In_2Se_3$ material was obtained over 2-inches c-sapphire wafers using molecular beam epitaxy (MBE). Excellent quality of thick (90 nm) and very thin films, down to two quintuple layers (2…
This article reviews experimental work on the ultrafast electron dynamics in the topological surface state (TSS) of three-dimensional (3D) topological insulators (TIs) observed with time- and angle-resolved two-photon photoemission (2PPE).…
We report a large third order nonlinear optical response of palladium diselenide (PdSe2) films, a two dimensional (2D) noble metal dichalcogenide material. Both open aperture (OA) and closed aperture (CA) Z scan measurements are performed…
Nonlinear spectroscopic techniques using entangled photon pairs can provide an opportunity to exploit non-classical correlations encoded in two-photon wavefunctions to manipulate two-exciton wavefunctions. We propose an entangled photon…
We report on the coherent phonon spectroscopy of polymorphic $\mathrm{MoTe_2}$ single crystals using a femtosecond-pulsed laser to investigate the relationship between structural phase transitions and photo-thermal effects induced by…
We present a systematic study of ultrafast all-optical switching of Si photonic band gap woodpile crystals using broadband tunable nondegenerate pump-probe spectroscopy. At pump-probe coincidence, we investigate the behavior the…
We describe a setup for time- and angle-resolved photoemission spectroscopy with wavelength-tunable excitation and extreme ultraviolet probe. It is enabled by using the 10 kHz twin Ti:sapphire amplifiers seeded by the common Ti:sapphire…
Measurements of the phase of two-photon matrix elements are presented for resonant and antiresonant two-color ionization of helium. A tunable, narrow-bandwidth, near-infrared (NIR) laser source is used for extreme ultra-violet (XUV)…
A nondegenerate four-level N-type scheme was experimentally implemented to observe electromagnetically induced transparency (EIT) at the $^{87}$Rb D$_{2}$ line. Radiations of two independent external-cavity semiconductor lasers were used in…
We propose a novel scheme for the population and depletion of nuclear isomers. The scheme combines the $\gamma$-photons with energies $\gtrsim 10$ keV emitted during the interaction of a contemporary high-intensity laser pulse with a plasma…
We describe the colloidal hot-injection synthesis of phase-pure nanocrystals (NCs) of a highly abundant mineral, chalcopyrite (CuFeS2). Absorption bands centered at around 480 and 950 nm, spanning almost the entire visible and near infrared…
We report time-resolved photoelectron spectroscopy of the $3s3p$ doubly excited states of helium dressed by an intense near-infrared (NIR) laser field. Using synchronized XUV free-electron-laser and 800-nm NIR laser pulses, we observe a…
Fundamental to all living organisms and living soft matter are emergent processes in which the reorganization of individual constituents at the nanoscale drives group-level movements and shape changes at the macroscale over time. However,…
We introduce a superresolution technique that combines spatial mode demultiplexing (SPADE) with emitter blinking. We show that temporal fluctuations not only enhance the precision of SPADE imaging, but also drastically simplify the…
We present a rapid-scanning approach to fluorescence-detected two-dimensional electronic spectroscopy that combines acousto-optic phase-modulation with digital lock-in detection. The approach shifts the signal detection window to suppress…
Within optical quantum information processing, single-photon sources based on a two-level system in a semiconductor material allow for on-demand generation of single photons. To initiate the spontaneous emission process, it is necessary to…
It has been proposed that entangled two-photon absorption (E2PA) can be observed with up to 10 orders of magnitude lower photon flux than its classical counterpart. However, there is a significant controversy regarding the magnitude of this…
We present a systematic investigation of two-photon excitation processes in a GaAs-based microcavity in the strong-coupling regime. We observe second harmonic generation resonant to the upper and lower polariton level, which exhibits a…