An optical implementation of iterative fractional Fourier transform algorithm is proposed and demonstrated. In the proposed implementation, the phase-shifting digital holography technique and the phase-type spatial light modulator are adopted for the measurement and the modulation of complex optical fields, respectively. With the devised iterative fractional Fourier transform system, we demonst...

One-dimensional Fast Fourier Transform (FFT) operations work fastest on grids whose size is divisible by a power of two. Because of this, padding grids (that are not already sized to a power of two) so that their size is the next highest power of two can speed up operations. While this works well for one-dimensional grids, it does not work well for two-dimensional grids. For a two-dimensional g...

In the accompaning Letter [ I] we have described successful FT-ESR imaging experiments utilizing pulsed field gradients. It was shown that the phase encoding method is the preferred one, and it yields spectral-spatial images of a quality comparable to the best cw-ESR spectral-spatial images even though it is only at an early stage of development. The realization of these FT-ESR imaging experime...

We introduce two-dimensional NMR spectroscopy detected by recording and processing the noise originating from nuclei that have not been subjected to any radio frequency excitation. The method relies on cross-correlation of two noise blocks that bracket the evolution and mixing periods. While the sensitivity of the experiment is low in conventional NMR setups, spin-noise-detected NMR spectroscop...

Coherent light-matter interactions of direct-gap semiconductor nanostructures provide a great test system for fundamental research into quantum electronics and many-body physics. The understanding gained from studying these interactions can facilitate the design of optoelectronic devices. Recently, we have used optical two-dimensional Fourier-transform spectroscopy to explore coherent light-mat...

Two-dimensional Fourier-transform ESR spectra from a complex fluid characterized by very short free induction decay times are reported. They provide enhanced resolution to dynamic molecular structure compared to conventional cw-ESR spectra which are inhomogeneously broadened by the macroscopic disorder. A general theoretical analysis based on the stochastic Liouville equation permits us to accu...

a School of Mathematical Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia e-mail: [email protected] 1 Department of Mathematics, Hasanuddin University, KM 10 Tamalanrea Makassar, Indonesia b Department of Applied Physics, University of Fukui, 910-8507 Fukui, Japan e-mail: [email protected] c Division of Mathematical Sciences, Osaka Kyoiku University, Osaka 582-8582, Japa...

There is continuous research effort into the expansion and refinement of transform techniques for audio signal processing needs, yet the two-dimensional Fourier transform has seldom been applied to audio. This is probably because audio does not readily allow the application of a 2D transform, unlike images for which its use is common. A signal mapping is first required to obtain a two-dimension...

Respiratory and other regular motions during two-dimensional Fourier transform magnetic resonance imaging produce image artifacts consisting of local blurring and more or less regularly spaced "ghost" images propagating along the direction of the phase-encoding magnetic field gradient. The patterns of these ghost artifacts can be understood in terms of the technique of image production and basi...