Optical two-dimensional Fourier transform spectroscopy with active interferometric stabilization

Abstract

Optical two-dimensional Fourier transform spectroscopy is implemented near 800 nm with active stabilization. Excitation pulse delay is stabilized during data acquisition and stepped with interferometric accuracy. The reference used for heterodyne detecting the complete transient four-wave mixing signal is also phase-stabilized. The phase evolution of the four-wave mixing signal during the initial evolution period and the final detection period is then measured and correlated. Two-dimensional spectra with absorption and emission frequency axes are obtained by Fourier transforms with respect to the corresponding time variables. Measurement performed on a GaAs multiple quantum well sample shows light-hole and heavy-hole exciton transitions as the diagonal peaks and coupling between these two resonances as off-diagonal peaks.

Polarization-dependent optical 2D Fourier transform spectroscopy of semiconductors

“…In addition, the delay between the reference beam and the k c is actively stabilized by monitoring the spatial fringes between them. The details of the active stabilization have been described (31).…”

Two-dimensional fluorescence-detected coherent spectroscopy with absolute phasing by confocal imaging of a dynamic grating and 27-step phase-cycling

“…In 2DCS, interaction of a bulk sample with three optical fields from three non-collinear phase-stable pulses generates a time-dependent macroscopic third-order (χ (3) ) polarization which emits a signal field in a backgroundfree direction by virtue of momentum conservation of optical fields; this is known as phase-matching. The phase-stability at optical frequencies is maintained by a variety of techniques, e.g., (1) interferometer with (i) passive phase-locking using diffractive optics, [2][3][4] (ii) active phase-locking using feedback electronics, 14 and (iii) inherently phase-stabilized geometry 15 and (2) (phase-only) pulse-shaping. 16 However, in a bulk sample ultrafast (coherent) dynamics is often obscured by inhomogeneous dephasing due to a) E-mail: akde@lbl.gov b) Present address: Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA.…”

Multidimensional coherent optical spectroscopy of semiconductor nanostructures: a review

“…Although not the most straightforward to implement, the 'box' geometry [15,31,32,33,34,35] ( Fig. 8 (a)) is versatile and conceptually easy to understand.…”

“…The signal is spectrally resolved by a grating-based spectrometer on a CCD camera -providing, in a single acquisition, the Fourier transform of the signal with respect to emission time t. Phase resolution is obtained through spectral interferometry [36], where the signal is heterodyned with a reference pulse (local oscillator (LO)). The LO can either be routed around the sample [33,34] or through the sample [31,35], in which case the amplitude and phase distortion of the LO needs to be accounted and compensated for [37]. Based on a similar principle, the use of the box geometry in a reflection geometry has also been demonstrated [38], and can be used in the case of optically dense samples.…”

“…A cw reference laser runs through the setup, and is reflected back using a dichroic mirror (DCM) to form three nested Michelson interferometers. Stabilization of inter-pulse delays is ensured by monitoring the reference laser interference on reference detectors (REF) [33,34].…”