Lock-in amplifiers as a platform for weak signal measurements: Development and applications

Q Zhang, W Jeong, DJ Kang - Current Applied Physics, 2024‏ - Elsevier
The accuracy of modern scientific research and technological advancement is highly reliant
on the ability to accurately measure weak signals. The lock-in amplifier (LIA) represents an …

Advances in nonlinear spectroscopy using phase modulated light fields: prospective applications in perturbative and non-perturbative regimes

KJ Karki, MF Ciappina - Advances in Physics: X, 2022‏ - Taylor & Francis
Since its first implementation in 2006, in fluorescence detected Fourier transform excitation
spectroscopy of rubidium atoms, phase modulation is being increasingly used in nonlinear …

Vibronic coherence contributes to photocurrent generation in organic semiconductor heterojunction diodes

Q Bian, F Ma, S Chen, Q Wei, X Su, IA Buyanova… - Nature …, 2020‏ - nature.com
Charge separation dynamics after the absorption of a photon is a fundamental process
relevant both for photosynthetic reaction centers and artificial solar conversion devices. It …

Before Förster. Initial excitation in photosynthetic light harvesting

KJ Karki, J Chen, A Sakurai, Q Shi, AT Gardiner… - Chemical …, 2019‏ - pubs.rsc.org
Electronic 2D spectroscopy allows nontrivial quantum effects to be explored in
unprecedented detail. Here, we apply recently developed fluorescence detected coherent …

Interpreting fluorescence detected two-dimensional electronic spectroscopy

O Kuhn, T Mančal, T Pullerits - The Journal of Physical Chemistry …, 2020‏ - ACS Publications
Electronic coherent multidimensional spectroscopy (CMDS) allows detailed studies of
ultrafast dynamics in systems with highly congested complicated spectral bands. 1− 3 A …

Phase-synchronous detection of coherent and incoherent nonlinear signals

KJ Karki, L Kringle, AH Marcus, T Pullerits - Journal of Optics, 2015‏ - iopscience.iop.org
The nonlinear optical response of a material system contains detailed information about its
electronic structure. Standard approaches to nonlinear spectroscopy often use multiple …

Coherent multidimensional spectroscopy in the gas phase

L Bruder, U Bangert, M Binz, D Uhl… - Journal of Physics B …, 2019‏ - iopscience.iop.org
Recent work applying multidimentional coherent electronic spectroscopy at dilute samples
in the gas phase is reviewed. The development of refined phase cycling approaches with …

Evidence of high-order nonlinearities in supercontinuum white-light generation from a gold nanofilm

J Chen, A Krasavin, P Ginzburg, AV Zayats… - ACS …, 2018‏ - ACS Publications
White-light supercontinuum generation can be readily observed when gold nanostructures
are irradiated with short pulses of light. It is believed that the nanostructures enhance the …

Differentiation of true nonlinear and incoherent mixing of linear signals in action-detected 2D spectroscopy

AAS Kalaee, F Damtie, KJ Karki - The Journal of Physical …, 2019‏ - ACS Publications
Phase modulation and phase cycling schemes have been commonly used in electronic two-
dimensional (2D) spectroscopy where the observables are incoherent signals such as …

Directional spectral emissivity measurement approach in a broad-spectrum at low temperatures: Device and methodology study

Z Yuan, L Li, K Yu, K Zhang, Y Liu - Measurement, 2024‏ - Elsevier
Accurate spectral emissivity is indispensable for driving the development of radiative cooling
and radiative thermal camouflage toward low temperatures. Nevertheless, the measurement …