Ultrafast quantum control of ionization dynamics

Clear spectroscopic signatures of ligand field states in the MLCT decay cascade of trans-[Ru(L)4(NCS)2] (L = pyridine or 4-methoxypyridine) were found. (TD)DFT calculations reveal the presence of both MLCT and LMCT transient absorption bands.

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Doping glow-discharge amorphous silicon by metal coevaporation

Canadian Journal of Physics ◽

10.1139/p87-167 ◽

1987 ◽

Vol 65 (8) ◽

pp. 1027-1029 ◽

Cited By ~ 1

Author(s):

G. Perluzzo ◽

C. Aktik ◽

J. F. Currie ◽

S. Poulin-Dandurand ◽

A. Yelon ◽

...

Keyword(s):

Glow Discharge ◽

Amorphous Silicon ◽

Mass Spectroscopy ◽

Thermal Evaporation ◽

New Technique ◽

A New Technique ◽

And Control ◽

Further Development ◽

Monitor And Control

We report here on the further development of a new technique for doping plasma-deposited amorphous silicon by thermal evaporation of metal into the plasma from which the film is grown. We show that the de bias applied to the substrate has an important effect on the incorporation of the metal into the film, and on the doping efficiency. We also report on our efforts to monitor and control the evaporation by mass spectroscopy.

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Diffusion of P- and N-Type Dopants in GaAs/AIGaAs DH Structure Grown by MOCVD

MRS Proceedings ◽

10.1557/proc-240-733 ◽

1991 ◽

Vol 240 ◽

Author(s):

N. Ogasawara ◽

S. Karakida ◽

M. Miyashita ◽

N. Hayafuji ◽

M. Tsugami ◽

...

Keyword(s):

Optical Properties ◽

Mass Spectroscopy ◽

Laser Diodes ◽

Doping Profile ◽

Electrical And Optical Properties ◽

Si Doped ◽

And Control ◽

Cladding Layers ◽

Secondary Ion ◽

Undoped Gaas

ABSTRACTMost of AIGaAs laser diodes (LDs) contain the doublehetero (DH) structure. The DH structure consists of AIGaAs layers with high Al composition as cladding layers and undoped GaAs or AIGaAs with low Al composition. Therefore, it is important for improvement of device characteristics to understand and control the diffusion of dopants. However, most work on the diffusion of dopants have been carried out on the diffusion in GaAs. In this paper, we compared electrical and optical properties of Si-doped AIGaAs with those of Se-doped AIGaAs and investigated the diffusion of Si, Se and Zn in the GaAs/Al0.48Ga0.52As DH structure by secondary ion mass spectroscopy (SIMS). Doping profile of Si is controllable rather than that of Se. However, from the viewpoint of device characteristics, Se is more suitable than Si.

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Demonstration of non-Markovian process characterisation and control on a quantum processor

Nature Communications ◽

10.1038/s41467-020-20113-3 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 2

Author(s):

G. A. L. White ◽

C. D. Hill ◽

F. A. Pollock ◽

L. C. L. Hollenberg ◽

K. Modi

Keyword(s):

Quantum Control ◽

Scale Up ◽

Coherence Time ◽

Error Type ◽

Markovian Dynamics ◽

Quantum Device ◽

Significant Step ◽

Quantum Technology ◽

And Control ◽

Device Operation

AbstractIn the scale-up of quantum computers, the framework underpinning fault-tolerance generally relies on the strong assumption that environmental noise affecting qubit logic is uncorrelated (Markovian). However, as physical devices progress well into the complex multi-qubit regime, attention is turning to understanding the appearance and mitigation of correlated — or non-Markovian — noise, which poses a serious challenge to the progression of quantum technology. This error type has previously remained elusive to characterisation techniques. Here, we develop a framework for characterising non-Markovian dynamics in quantum systems and experimentally test it on multi-qubit superconducting quantum devices. Where noisy processes cannot be accounted for using standard Markovian techniques, our reconstruction predicts the behaviour of the devices with an infidelity of 10−3. Our results show this characterisation technique leads to superior quantum control and extension of coherence time by effective decoupling from the non-Markovian environment. This framework, validated by our results, is applicable to any controlled quantum device and offers a significant step towards optimal device operation and noise reduction.

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The roles of drift and control field constraints upon quantum control speed limits

New Journal of Physics ◽

10.1088/1367-2630/aa8242 ◽

2017 ◽

Vol 19 (10) ◽

pp. 103015 ◽

Cited By ~ 9

Author(s):

Christian Arenz ◽

Benjamin Russell ◽

Daniel Burgarth ◽

Herschel Rabitz

Keyword(s):

Quantum Control ◽

Control Field ◽

Speed Limits ◽

And Control

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Characterization and control of open quantum systems beyond quantum noise spectroscopy

npj Quantum Information ◽

10.1038/s41534-020-00332-8 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Akram Youssry ◽

Gerardo A. Paz-Silva ◽

Christopher Ferrie

Keyword(s):

Quantum Control ◽

Performance Metrics ◽

Quantum Noise ◽

Open Quantum Systems ◽

Power Spectra ◽

General Purpose ◽

Noise Power ◽

Noise Spectroscopy ◽

Quantum Technology ◽

And Control

AbstractThe ability to use quantum technology to achieve useful tasks, be they scientific or industry related, boils down to precise quantum control. In general it is difficult to assess a proposed solution due to the difficulties in characterizing the quantum system or device. These arise because of the impossibility to characterize certain components in situ, and are exacerbated by noise induced by the environment and active controls. Here, we present a general purpose characterization and control solution making use of a deep learning framework composed of quantum features. We provide the framework, sample datasets, trained models, and their performance metrics. In addition, we demonstrate how the trained model can be used to extract conventional indicators, such as noise power spectra.

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Control of Metal Alloy Oxidation with Electric Fields

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071260 ◽

1973 ◽

Vol 31 ◽

pp. 164-165

Author(s):

R. R. Dils ◽

P. S. Follansbee

Keyword(s):

Electric Fields ◽

Oxidation Process ◽

Base Alloy ◽

Oxide Surface ◽

Platinum Electrodes ◽

Insulating Layer ◽

Iron Base Alloy ◽

Alloy Oxidation ◽

Aluminum Oxide Layer ◽

And Control

Electric fields have been applied across oxides growing on a high temperature alloy and control of the oxidation of the material has been demonstrated. At present, three-fold increases in the oxidation rate have been measured in accelerating fields and the oxidation process has been completely stopped in a retarding field.The experiments have been conducted with an iron-base alloy, Pe 25Cr 5A1 0.1Y, although, in principle, any alloy capable of forming an adherent aluminum oxide layer during oxidation can be used. A specimen is polished and oxidized to produce a thin, uniform insulating layer on one surface. Three platinum electrodes are sputtered on the oxide surface and the specimen is reoxidized.

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Evidence for a Blood Ganglion Barrier in the Superior Cervical Ganglion of the Rat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053681 ◽

1982 ◽

Vol 40 ◽

pp. 204-204

Author(s):

D. M. DePace

Keyword(s):

Blood Vessels ◽

Superior Cervical Ganglion ◽

Peripheral Nerves ◽

Time Schedule ◽

Transmission Electron ◽

Cervical Ganglion ◽

The Central Nervous System ◽

Cervical Ganglia ◽

Capillary Circulation ◽

And Control

The majority of blood vessels in the superior cervical ganglion possess a continuous endothelium with tight junctions. These same features have been associated with the blood brain barrier of the central nervous system and peripheral nerves. These vessels may perform a barrier function between the capillary circulation and the superior cervical ganglion. The permeability of the blood vessels in the superior cervical ganglion of the rat was tested by intravenous injection of horseradish peroxidase (HRP). Three experimental groups of four animals each were given intravenous HRP (Sigma Type II) in a dosage of.08 to.15 mg/gm body weight in.5 ml of.85% saline. The animals were sacrificed at five, ten or 15 minutes following administration of the tracer. Superior cervical ganglia were quickly removed and fixed by immersion in 2.5% glutaraldehyde in Sorenson's.1M phosphate buffer, pH 7.4. Three control animals received,5ml of saline without HRP. These were sacrificed on the same time schedule. Tissues from experimental and control animals were reacted for peroxidase activity and then processed for routine transmission electron microscopy.

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Effects of renovascular hypertension on rat adrenal zona glomerulosa

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083783 ◽

1978 ◽

Vol 36 (2) ◽

pp. 582-583

Author(s):

G. Mazzocchi ◽

P. Rebuffat ◽

C. Robba ◽

P. Vassanelli ◽

G. G. Nussdorfer

Keyword(s):

Renovascular Hypertension ◽

Left Kidney ◽

Renin Angiotensin System ◽

Plasma Renin ◽

Zona Glomerulosa ◽

Ultrastructural Changes ◽

Albino Rats ◽

Left Renal Artery ◽

Angiotensin System ◽

And Control

It is well known that the rat adrenal zona glomerulosa steroidogenic activity is controlled by the renin-angiotensin system. The ultrastructural changes in the rat zona glomerulosa cells induced by renovascular hypertension were described previously, but as far as we are aware no correlated biochemical and morphometric investigations were performed.Twenty adult male albino rats were divided into 2 experimental groups. One group was subjected to restriction of blood flow to the left kidney by the application of a silver clip about the left renal artery. The other group was sham-operated and served as a control. Renovascular hypertension developed in about 10 days: sistolic blood pressure averaged 165 ± 6. 4 mmHg, whereas it was about 110 ± 3. 8 mmHg in the control animals. The hypertensive and control rats were sacrificed 20 days after the operation. The blood was collected and plasma renin activity was determined by radioimmunological methods. The aldosterone concentration was radioimmunologically assayed both in the plasma and in the homogenate of the left capsular adrenal gland.

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X-Ray Replication of Submicrometer Linewidth Patterns

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078250 ◽

1977 ◽

Vol 35 ◽

pp. 136-137

Author(s):

Henry I. Smith ◽

D.C. Flanders

Keyword(s):

Electron Beam Lithography ◽

Cross Sectional ◽

X Ray ◽

Electron Backscattering ◽

Spatial Frequencies ◽

Cross Sectional Profile ◽

Carbon Foils ◽

Sectional Profile ◽

And Control ◽

Soft Radiation

Scanning electron beam lithography has been used for a number of years to write submicrometer linewidth patterns in radiation sensitive films (resist films) on substrates. On semi-infinite substrates, electron backscattering severely limits the exposure latitude and control of cross-sectional profile for patterns having fundamental spatial frequencies below about 4000 Å(l),Recently, STEM'S have been used to write patterns with linewidths below 100 Å. To avoid the detrimental effects of electron backscattering however, the substrates had to be carbon foils about 100 Å thick (2,3). X-ray lithography using the very soft radiation in the range 10 - 50 Å avoids the problem of backscattering and thus permits one to replicate on semi-infinite substrates patterns with linewidths of the order of 1000 Å and less, and in addition provides means for controlling cross-sectional profiles. X-radiation in the range 4-10 Å on the other hand is appropriate for replicating patterns in the linewidth range above about 3000 Å, and thus is most appropriate for microelectronic applications (4 - 6).

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