scholarly journals Connection between Inverse Engineering and Optimal Control in Shortcuts to Adiabaticity

Entropy ◽  
2021 ◽  
Vol 23 (1) ◽  
pp. 84
Author(s):  
Qi Zhang ◽  
Xi Chen ◽  
David Guéry-Odelin
Keyword(s):  
Optimal Control ◽  
Quantum Control ◽  
Cold Atoms ◽  
Spin Dynamics ◽  
Harmonic Trap ◽  
High Fidelity ◽  
Physical Constraints ◽  
Atomic Transport ◽  
Shortcuts To Adiabaticity ◽  
Very High

We consider fast high-fidelity quantum control by using a shortcut to adiabaticity (STA) technique and optimal control theory (OCT). Three specific examples, including expansion of cold atoms from the harmonic trap, atomic transport by moving harmonic trap, and spin dynamics in the presence of dissipation, are explicitly detailed. Using OCT as a qualitative guide, we demonstrate how STA protocols designed from inverse engineering method can approach with very high precision optimal solutions built about physical constraints, by a proper choice of the interpolation function and with a very reduced number of adjustable parameters.

scholarly journals Experimental implementation of precisely tailored light-matter interaction via inverse engineering

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Ying Yan ◽  
Chunyan Shi ◽  
Adam Kinos ◽  
Hafsa Syed ◽  
Sebastian P. Horvath ◽  
...  
Keyword(s):  
Quantum Dynamics ◽  
Quantum Control ◽  
Quantum Information Processing ◽  
Rare Earth Ions ◽  
Adiabatic Process ◽  
Physical Constraints ◽  
Shortcuts To Adiabaticity ◽  
Experimental Implementation ◽  
Speed Up ◽  
Light Matter Interaction

AbstractAccurate and efficient quantum control in the presence of constraints and decoherence is a requirement and a challenge in quantum information processing. Shortcuts to adiabaticity, originally proposed to speed up the slow adiabatic process, have nowadays become versatile toolboxes for preparing states or controlling the quantum dynamics. Unique shortcut designs are required for each quantum system with intrinsic physical constraints, imperfections, and noise. Here, we implement fast and robust control for the state preparation and state engineering in a rare-earth ions system. Specifically, the interacting pulses are inversely engineered and further optimized with respect to inhomogeneities of the ensemble and the unwanted interaction with other qubits. We demonstrate that our protocols surpass the conventional adiabatic schemes, by reducing the decoherence from the excited-state decay and inhomogeneous broadening. The results presented here are applicable to other noisy intermediate-scale quantum systems.

scholarly journals Smooth bang-bang shortcuts to adiabaticity for atomic transport in a moving harmonic trap

2020 ◽  
Vol 101 (6) ◽  
Author(s):  
Yongcheng Ding ◽  
Tang-You Huang ◽  
Koushik Paul ◽  
Minjia Hao ◽  
Xi Chen
Keyword(s):  
Harmonic Trap ◽  
Atomic Transport ◽  
Shortcuts To Adiabaticity

Quantum control of entanglement in coupled spins using shortcuts to adiabaticity and optimal control

2019 ◽  
Author(s):  
Dionisis Stefanatos ◽  
Nikos Iliopoulos ◽  
Vasilos Karanikolas ◽  
Emmanuel Paspalakis
Keyword(s):  
Optimal Control ◽  
Quantum Control ◽  
Shortcuts To Adiabaticity

scholarly journals FEBID 3D-Nanoprinting at Low Substrate Temperatures: Pushing the Speed While Keeping the Quality

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1527
Author(s):  
Jakob Hinum-Wagner ◽  
David Kuhness ◽  
Gerald Kothleitner ◽  
Robert Winkler ◽  
Harald Plank
Keyword(s):  
Volume Growth ◽  
Point Of View ◽  
High Fidelity ◽  
Direct Write ◽  
General Picture ◽  
3D Space ◽  
Design Flexibility ◽  
Substrate Temperatures ◽  
Very High ◽  
Comprehensive Discussion

High-fidelity 3D printing of nanoscale objects is an increasing relevant but challenging task. Among the few fabrication techniques, focused electron beam induced deposition (FEBID) has demonstrated its high potential due to its direct-write character, nanoscale capabilities in 3D space and a very high design flexibility. A limitation, however, is the low fabrication speed, which often restricts 3D-FEBID for the fabrication of single objects. In this study, we approach that challenge by reducing the substrate temperatures with a homemade Peltier stage and investigate the effects on Pt based 3D deposits in a temperature range of 5–30 °C. The findings reveal a volume growth rate boost up to a factor of 5.6, while the shape fidelity in 3D space is maintained. From a materials point of view, the internal nanogranular composition is practically unaffected down to 10 °C, followed by a slight grain size increase for even lower temperatures. The study is complemented by a comprehensive discussion about the growth mechanism for a more general picture. The combined findings demonstrate that FEBID on low substrate temperatures is not only much faster, but practically free of drawbacks during high fidelity 3D nanofabrication.

High fidelity modeling tools for engine liner design and screening of advanced concepts

2021 ◽  
pp. 1475472X2110238
Author(s):  
Julian Winkler ◽  
Jeffrey M Mendoza ◽  
C Aaron Reimann ◽  
Kenji Homma ◽  
Jose S Alonso
Keyword(s):  
Aircraft Engine ◽  
High Fidelity ◽  
Treatment Area ◽  
Modeling Tools ◽  
Physical Constraints ◽  
Acoustic Performance ◽  
Acoustic Liner ◽  
Bias Flow ◽  
Honeycomb Cores ◽  
Acoustic Treatment

With aircraft engines trending toward ultra-high bypass ratios, resulting in lower fan pressure ratios, lower fan RPM, and therefore lower blade pass frequency, the aircraft engine liner design space has been dramatically altered. This result is also due to the associated reduction in both the available acoustic treatment area (axial extent) as well as thickness (liner depth). As a consequence, there is current need for novel acoustic liner technologies that are able to meet multiple physical constraints and simultaneously provide enhanced noise attenuation capabilities. In addition, recent advances in additive manufacturing have enabled the consideration of complex liner backing structures that would traditionally be limited to honeycomb cores. This paper provides an overview of engine liner modeling and a description of the key physical mechanisms, with some emphasis on the use of low to high-fidelity tools such as empirical models and commercially available software such as COMSOL, Actran, and PowerFLOW. It is shown that the higher fidelity tools are a critical enabler for the evaluation and construction of future complex liner structures. A systematic study is conducted to predict the acoustic performance of traditional single degree of freedom liners and comparisons are made to experimental data. The effects of grazing flow and bias flow are briefly addressed. Finally, a more advanced structure, a metamaterial, is modeled and the acoustic performance is discussed.

scholarly journals Dynamics of entanglement entropy of interacting fermions in a 1D driven harmonic trap

2018 ◽  
Vol 175 ◽  
pp. 03002
Author(s):  
Joshua R. McKenney ◽  
William J. Porter ◽  
Joaquín E. Drut
Keyword(s):  
Thermal Behavior ◽  
Parametric Resonance ◽  
Cold Atoms ◽  
Particle System ◽  
Entanglement Entropy ◽  
Harmonic Trap ◽  
Time Dependent ◽  
One Dimension ◽  
Recent Analysis ◽  
Contact Interactions

Following up on a recent analysis of two cold atoms in a time-dependent harmonic trap in one dimension, we explore the entanglement entropy of two and three fermions in the same situation when driven through a parametric resonance. We find that the presence of such a resonance in the two-particle system leaves a clear imprint on the entanglement entropy. We show how the signal is modified by attractive and repulsive contact interactions, and how it remains present for the three-particle system. Additionaly, we extend the work of recent experiments to demonstrate how restricting observation to a limited subsystem gives rise to locally thermal behavior.

scholarly journals Synthetic dimensions for cold atoms from shaking a harmonic trap

2017 ◽  
Vol 95 (2) ◽  
Author(s):  
Hannah M. Price ◽  
Tomoki Ozawa ◽  
Nathan Goldman
Keyword(s):  
Cold Atoms ◽  
Harmonic Trap
Sign in / Sign up

Export Citation Format

Share Document