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1.
We propose a new method of generating nonclassical optical field states. The method uses a semiconductor device, which consists of a single quantum dot as active medium embedded in a p- i- n junction and surrounded by a microcavity. Resonant tunneling of electrons and holes into the quantum dot ground states, together with the Pauli exclusion principle, produce regulated single photons or regulated pairs of photons. We propose that this device also has the unique potential to generate pairs of entangled photons at a well-defined repetition rate. 相似文献
2.
G. Di Nicola M. Moglie R. Stryjek G. Santori 《Journal of Thermal Analysis and Calorimetry》2011,105(2):489-493
A recently built experimental setup was employed for the estimation of the solid–liquid equilibria of alternative refrigerants systems. The behavior of dimethyl ether (DME) + carbon dioxide was measured down to temperatures of 131.6 K. To confirm the reliability of the apparatus, the triple point of the DME was measured. The triple point data measured revealed a good consistency with the literature. The results obtained for the mixtures were corrected by the Rossini method and interpreted by means of the Schröder equation. 相似文献
3.
M. Pelton C. Santori G.S. Solomon O. Benson Y. Yamamoto 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,18(2):179-190
Current quantum cryptography systems are limited by the attenuated coherent pulses they use as light sources: a security loophole
is opened up by the possibility of multiple-photon pulses. By replacing the source with a single-photon emitter, transmission
rates of secure information can be improved. We have investigated the use of single self-assembled InAs/GaAs quantum dots
as such single-photon sources, and have seen a tenfold reduction in the multi-photon probability as compared to Poissonian
pulses. An extension of our experiment should also allow for the generation of triggered, polarization-entangled photon pairs.
The utility of these light sources is currently limited by the low efficiency with which photons are collected. However, by
fabricating an optical microcavity containing a single quantum dot, the spontaneous emission rate into a single mode can be
enhanced. Using this method, we have seen 78% coupling of single-dot radiation into a single cavity resonance. The enhanced
spontaneous decay should also allow for higher photon pulse rates, up to about 3 GHz.
Received 8 July 2001 and Received in final form 25 August 2001 相似文献
4.
The successful fractionation of a mixture of monosaccharides using an immobilized lectin column operating under isocratic conditions is described. The key factors for effective separation were found to be sample size, feed velocity and column length. Under optimal conditions it was possible to obtain complete resolution of a mixture of L-arabinose, D-fructose and D-mannose in less than 40 min. 相似文献
5.
A. Arteconi G. Di Nicola M. Moglie G. Santori R. Stryjek 《Journal of Thermal Analysis and Calorimetry》2009,97(2):631-636
Dimethyl ether is an important chemical material and it has many engineering applications. It is a clean and economical alternative
fuel and an ozone-friendly refrigerant. In this work, its PVT properties have been object of study. In particular, the experimental work was performed both in the two-phase region and
in the superheated vapor region phase by means of the isochoric method. The isochoric measurements were carried out at temperatures
from 219 K to 363 K and at pressures from 22 kPa up to 1,740 kPa. A total of 159 points, both in the two phase (71 points)
and in the superheated vapor region (88 points) were obtained. The present experimental PVT data contribute to the deeper knowledge of the behaviour of the fluid both in the superheated vapour and in the saturation
pressure region and to the development of a new equation of state. 相似文献
6.
7.
Triggered single photons from a quantum dot 总被引:9,自引:0,他引:9
We demonstrate a new method for generating triggered single photons. After a laser pulse generates excitons inside a single quantum dot, electrostatic interactions between them and the resulting spectral shifts allow a single emitted photon to be isolated. Correlation measurements show a reduction of the two-photon probability to 0.12 times the value for Poisson light. Strong antibunching persists when the emission is saturated. The emitted photons are also polarized. 相似文献
8.
Boettcher SW Warren EL Putnam MC Santori EA Turner-Evans D Kelzenberg MD Walter MG McKone JR Brunschwig BS Atwater HA Lewis NS 《Journal of the American Chemical Society》2011,133(5):1216-1219
Arrays of B-doped p-Si microwires, diffusion-doped with P to form a radial n(+) emitter and subsequently coated with a 1.5-nm-thick discontinuous film of evaporated Pt, were used as photocathodes for H(2) evolution from water. These electrodes yielded thermodynamically based energy-conversion efficiencies >5% under 1 sun solar simulation, despite absorbing less than 50% of the above-band-gap incident photons. Analogous p-Si wire-array electrodes yielded efficiencies <0.2%, largely limited by the low photovoltage generated at the p-Si/H(2)O junction. 相似文献
9.
N.P. Kobayashi S.-Y. Wang C. Santori R.S. Williams 《Applied Physics A: Materials Science & Processing》2006,85(1):1-6
The epitaxial growth of nanometer-scale structures on non-single crystalline surfaces is proposed and demonstrated. Hydrogenated amorphous silicon was deposited onto an SiO2 surface by plasma-enhanced chemical vapor deposition. Indium phosphide was deposited on the amorphous silicon by low-pressure metalorganic chemical vapor deposition in the presence of colloidal gold particles as catalysts. Under specific growth conditions, the indium phosphide formed nanoneedles connected to a microcrystalline silicon film nucleated within the amorphous silicon during the growth of the nanoneedles. Transmission electron microscopy revealed the presence of two different crystallographic structures: zinc-blende and wurtzite. Micro-photoluminescence measurements at room temperature showed two peaks with substantial blue-shifts with respect to that of bulk zinc-blende indium phosphide. PACS 81.16.Hc; 81.07.Vb; 68.65.La 相似文献
10.
Development and optimization of a method for analyzing biodiesel mixtures with non-aqueous reversed phase liquid chromatography 总被引:2,自引:0,他引:2
Di Nicola G Pacetti M Polonara F Santori G Stryjek R 《Journal of chromatography. A》2008,1190(1-2):120-126
Biodiesel (a mixture of fatty acid esters) is normally analyzed using gas chromatography/flame ionization detection, as specified by the ASTM D6584 and EN14105 standards. This paper proposes a binary gradient method for analyzing biodiesel mixtures using non-aqueous reverse phase HPLC with a UV detector capable of overcoming the drawbacks of the gas chromatographic technique normally used. The new analytical method was developed by means of a statistical sensitivity analysis applied to the main parameters influencing the recording, using the full factorial design method combined with the Yates algorithm and the steepest ascent optimization procedure. The present study shows the influence of the main biodiesel mixture separation analysis parameters. The resulting tool proved valid for analyzing not only biodiesel but also any traces of unreacted oil. 相似文献