scholarly journals Experimental interference of uncorrelated photons

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Heonoh Kim ◽  
Osung Kwon ◽  
Han Seb Moon
Keyword(s):  
Quantum Interference ◽  
Single Photon ◽  
Quantum Effect ◽  
Photon Counting ◽  
Interference Phenomenon ◽  
Single Photon Counting ◽  
Two Photon ◽  
Quantum Interference Effect ◽  
The Individual ◽  
Photon States

AbstractThe distinguishing of the multiphoton quantum interference effect from the classical one forms one of the most important issues in modern quantum mechanics and experimental quantum optics. For a long time, the two-photon interference (TPI) of correlated photons has been recognized as a pure quantum effect that cannot be simulated with classical lights. In the meantime, experiments have been carried out to investigate the classical analogues of the TPI. In this study, we conduct TPI experiments with uncorrelated photons with different center frequencies from a luminescent light source, and we compare our results with the previous ones of correlated photons. The observed TPI fringe can be expressed in the form of three phase terms related to the individual single-photon and two-photon states, and the fringe pattern is strongly affected by the two single-photon-interference fringes and also by their visibilities. With the exception of essential differences such as valid and accidental coincidence events within a given resolving time and the two-photon spectral bandwidth, the interference phenomenon itself exhibits the same features for both correlated and uncorrelated photons in the single-photon counting regime.

scholarly journals Optical Estimation of Absolute Membrane Potential Using One- and Two-Photon Fluorescence Lifetime Imaging Microscopy

2021 ◽  
Author(s):  
Julia R. Lazzari-Dean ◽  
Evan W. Miller
Keyword(s):  
Membrane Potential ◽  
Fluorescence Lifetime ◽  
Single Photon ◽  
Photon Counting ◽  
Fluorescence Lifetime Imaging ◽  
Single Photon Counting ◽  
Two Photon ◽  
Lifetime Imaging ◽  
Wide Range ◽  
Relative Measurements

AbstractBackgroundMembrane potential (Vmem) exerts physiological influence across a wide range of time and space scales. To study Vmem in these diverse contexts, it is essential to accurately record absolute values of Vmem, rather than solely relative measurements.Materials & MethodsWe use fluorescence lifetime imaging of a small molecule voltage sensitive dye (VF2.1.Cl) to estimate mV values of absolute membrane potential.ResultsWe test the consistency of VF2.1.Cl lifetime measurements performed on different single photon counting instruments and find that they are in striking agreement (differences of <0.5 ps/mV in the slope and <50 ps in the y-intercept). We also demonstrate that VF2.1.Cl lifetime reports absolute Vmem under two-photon (2P) illumination with better than 20 mV of Vmem resolution, a nearly 10-fold improvement over other lifetime-based methods.ConclusionsWe demonstrate that VF-FLIM is a robust and portable metric for Vmem across imaging platforms and under both one-photon and two-photon illumination. This work is a critical foundation for application of VF-FLIM to record absolute membrane potential signals in thick tissue.

TWO-PHOTON CORRELATION OF CHAOTIC LIGHT: A QUANTUM INTERFERENCE PHENOMENON

2007 ◽  
Vol 05 (01n02) ◽  
pp. 131-141
Author(s):  
YANHUA SHIH ◽  
GIULIANO SCARCELLI ◽  
VINCENZO BERARDI
Keyword(s):  
Quantum Interference ◽  
Quantum Effect ◽  
Statistical Correlation ◽  
Ghost Imaging ◽  
Photon Correlation ◽  
Interference Phenomenon ◽  
Phase Conjugate ◽  
Two Photon ◽  
Imaging Experiment ◽  
Phase Conjugate Mirror

Two-photon correlation phenomena of chaotic light, including the historical Hanbury Brown and Twiss effect, are essentially the quantum effect of two-photon interference, instead of the classical statistical correlation between intensity fluctuations. To support our view, we analyze a "ghost" imaging experiment with chaotic light for which the classical understanding does not give a satisfactory interpretation. We also provide a two-photon optical picture of ghost imaging with chaotic light in terms of a two-photon phase-conjugate mirror, which suggests lensless imaging applications for radiations for which no effective lens is available.

scholarly journals Single-photon-counting detector for increased sensitivity in two-photon laser scanning microscopy

2008 ◽  
Vol 33 (24) ◽  
pp. 2895 ◽  
Author(s):  
Richard K. P. Benninger ◽  
William J. Ashby ◽  
Elisabeth A. Ring ◽  
David W. Piston
Keyword(s):  
Laser Scanning ◽  
Single Photon ◽  
Photon Counting ◽  
Laser Scanning Microscopy ◽  
Scanning Microscopy ◽  
Single Photon Counting ◽  
Photon Counting Detector ◽  
Two Photon ◽  
Increased Sensitivity

Picosecond Tryptophan Fluorescence of Human Blood Serum Orosomucoid

1996 ◽  
Vol 61 (5) ◽  
pp. 808-818 ◽  
Author(s):  
Martin Hof ◽  
Stefan Vajda ◽  
Vlastimil Fidler ◽  
Vladimír Karpenko
Keyword(s):  
Single Photon ◽  
Global Analysis ◽  
Photon Counting ◽  
Tryptophan Fluorescence ◽  
Fluorescence Decay ◽  
Amino Acid Residues ◽  
Counting System ◽  
Single Photon Counting ◽  
Decay Behaviour ◽  
The Individual

The state of three tryptophyl residues in human serum orosomucoid was estimated by prediction methods based on parameters characterizing their hydrophobicity either directly, or in terms of buried surfaces of the individual amino acid residues. It is shown that tryptophan 25 is the most buried, while Trp 160 is the most exposed to the solvent. Trp 122 is in this respect in an intermediate state. The fluorescence decay behaviour was determined using a picosecond single photon counting system. The multiwavelength data were analyzed using a global analysis as well as a distribution of lifetimes program. Both procedures yielded the existence of four wavelength independent lifetimes (0.22 ns, 1.0 ns, 2.5 ns, and 8.4 ns). A tentative assignment of the decay associated spectra of the four components to the three individual tryptophans is presented.

scholarly journals Two-photon fluorescence lifetime for label-free microfluidic droplet sorting

2021 ◽  
Author(s):  
Sadat Hasan ◽  
Maximilian E. Blaha ◽  
Sebastian K. Piendl ◽  
Anish Das ◽  
David Geissler ◽  
...  
Keyword(s):  
Fluorescence Lifetime ◽  
Single Photon ◽  
Photon Counting ◽  
Droplet Microfluidics ◽  
Label Free ◽  
Single Photon Counting ◽  
Two Photon ◽  
Deep Uv ◽  
Droplet Sorting ◽  
532 Nm

AbstractMicrofluidic droplet sorting systems facilitate automated selective micromanipulation of compartmentalized micro- and nano-entities in a fluidic stream. Current state-of-the-art droplet sorting systems mainly rely on fluorescence detection in the visible range with the drawback that pre-labeling steps are required. This limits the application range significantly, and there is a high demand for alternative, label-free methods. Therefore, we introduce time-resolved two-photon excitation (TPE) fluorescence detection with excitation at 532 nm as a detection technique in droplet microfluidics. This enables label-free in-droplet detection of small aromatic compounds that only absorb in a deep-UV spectral region. Applying time-correlated single-photon counting, compounds with similar emission spectra can be distinguished due to their fluorescence lifetimes. This information is then used to trigger downstream dielectrophoretic droplet sorting. In this proof-of-concept study, we developed a polydimethylsiloxane-fused silica (FS) hybrid chip that simultaneously provides a very high optical transparency in the deep-UV range and suitable surface properties for droplet microfluidics. The herein developed system incorporating a 532-nm picosecond laser, time-correlated single-photon counting (TCSPC), and a chip-integrated dielectrophoretic pulsed actuator was exemplarily applied to sort droplets containing serotonin or propranolol. Furthermore, yeast cells were screened using the presented platform to show its applicability to study cells based on their protein autofluorescence via TPE fluorescence lifetime at 532 nm. Graphical abstract

Coherent state truncation by conditional interferometry

2020 ◽  
Vol 35 (19) ◽  
pp. 2050158
Author(s):  
Xue-Xiang Xu ◽  
Hong-Chun Yuan
Keyword(s):  
Coherent State ◽  
Single Photon ◽  
Photon Counting ◽  
Two Photon ◽  
Ideal State ◽  
Conditional State ◽  
Antibunching Effect ◽  
The One ◽  
Photon States ◽  
The Ideal

Based on a conditional interferometry proposed by Paris [Phys. Rev. A 62, 033813 (2000)], we prepare any chosen superposition of the vacuum, one-photon, and two-photon states, which is truncating from an input coherent state. Feeding two perfect single-photon states and a coherent state into the interferometry and employing two one-photon detections, the conditional state can be obtained in the signal port. Ideal and realistic features of the one-photon counting are taken into account together with the effect on the fidelity between the ideal state and the realistic case. The ideal state is just a particular case of the realistic state with the unit efficiency. We study the antibunching effect and Wigner function of the generated states. The results show that the generated states will exhibit their specular character.

Sign in / Sign up

Export Citation Format

Share Document