A versatile ultrastable platform for optical multidimensional Fourier-transform spectroscopy

Abstract

The JILA multidimensional optical nonlinear spectrometer (JILA-MONSTR) is a robust, ultrastable platform consisting of nested and folded Michelson interferometers that can be actively phase stabilized. This platform generates a square of identical laser pulses that can be adjusted to have arbitrary time delay between them while maintaining phase stability. The JILA-MONSTR provides output pulses for nonlinear excitation of materials and phase-stabilized reference pulses for heterodyne detection of the induced signal. This arrangement is ideal for performing coherent optical experiments, such as multidimensional Fourier-transform spectroscopy, which records the phase of the nonlinear signal as a function of the time delay between several of the excitation pulses. The resulting multidimensional spectrum is obtained from a Fourier transform. This spectrum can resolve, separate, and isolate coherent contributions to the light-matter interactions associated with electronic excitation at optical frequencies. To show the versatility of the JILA-MONSTR, several demonstrations of two-dimensional Fourier-transform spectroscopy are presented, including an example of a phase-cycling scheme that reduces noise. Also shown is a spectrum that accesses two-quantum coherences, where all excitation pulses require phase locking for detection of the signal.

Correlation and dephasing effects on the non-radiative coherence between bright excitons in an InAs QD ensemble measured with 2D spectroscopy

“…The experimental setup, shown in Fig. 2, is based on three-pulse transient FWM with the addition of interferometric stabilization of the pulse delays [26]. 150-fs pulses with wave vectors k a , k b and k c are focused onto the sample to generate a FWM signal in the direction k s = −k a + k b + k c .…”

Quantum beats due to excitonic ground-state splitting in colloidal quantum dots

“…In particular, in the optical frequency range minute mechanical drifts can lead to significant phase drifts comparable to the wavelength that would lead to inadequate 2DFT spectra. However, instrumentation developed recently consisting of an ultrastable platform of nested and folded Michelson interferometers that can be actively phase stabilized can overcome these challenges 5 . The advantages of multidimensional spectroscopy are well documented in the literature 6 .…”

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.…”

“…This direction ensures that pulse A is acting as the conjugate pulse in the sequence. Rephasing, nonrephasing or two-quantum signals can be selectively obtained by having the conjugated pulse A * arriving on the sample in the first, second or third position [15,34,35]. 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)).…”