2012年诺贝尔物理奖获得者大卫-维因兰德(Wineland)代表作

Quantum dynamics of single trapped ions

D.Leibfried

University of Colorado and National Institute of Standards and Technology,Boulder,

Colorado80305-3328

R.Blatt

Institut fu¨r Experimentalphysik,Universita¨t Innsbruck,A-6020Innsbruck,Austria

C.Monroe

FOCUS Center and Department of Physics,University of Michigan,Ann Arbor,

Michigan48109-1120

D.Wineland

National Institute of Standards and Technology,Boulder,Colorado80305-3328

(Published10March2003)

Single trapped ions represent elementary quantum systems that are well isolated from the environment.They can be brought nearly to rest by laser cooling,and both their internal electronic states and external motion can be coupled to and manipulated by lightfields.This makes them ideally suited for quantum-optical and quantum-dynamical studies under well-controlled conditions.

Theoretical and experimental work on these topics is reviewed in the paper,with a focus on ions trapped in radio-frequency(Paul)traps.

CONTENTS

I.Introduction282

II.Radio-Frequency Traps for Single Charged Particles283

A.Classical motion of charged particles in rf traps283

1.Classical equations of motion283

2.Lowest-order approximation284

3.Typical realizations285

B.Quantum-mechanical motion of charged

particles in rf traps285

1.Quantum-mechanical equations of motion286

2.Lowest-order quantum approximation287

C.Special quantum states of motion in ion traps287

1.The number operator and its eigenstates287

2.Coherent states288

3.Squeezed vacuum states288

4.Thermal distribution289 III.Trapped Two-Level Atoms Coupled to Light Fields289

A.The two-level approximation290

B.Theoretical description of the coupling290

1.Total Hamiltonian and interaction

Hamiltonian290

2.Rabi frequencies291

mb-Dicke regime292

4.Resolved sidebands292

5.Unresolved sidebands293

6.Spectrum of resonancefluorescence293

C.Detection of internal states294

1.The electron shelving method294

2.Experimental observations of quantum

jumps295

D.Detection of motional-state populations295 ser Cooling of Ions296

A.Doppler cooling296

B.Resolved-sideband cooling298

1.Theory298

2.Experimental results299

C.Electromagnetically induced transparency

cooling300

1.Cooling in the Lamb-Dicke regime301

2.Scattering rates in EIT cooling302

3.Experimental results303

V.Resonance Fluorescence of Single Ions303

A.Excitation spectroscopy,line shapes303

B.Nonclassical statistics,antibunching,and

squeezing304

C.Spectrum of resonancefluorescence,homodyne

detection offluorescence305 VI.Engineering and Reconstruction of Quantum States

of Motion307

A.Creation of special states of motion and

internal-state/motional-state entanglement307

1.Creation of number states307

2.Creation of coherent states308

3.Creation of squeezed states310

4.‘‘Schro¨dinger-cat’’states of motion310

5.Arbitrary states of motion312

B.Full determination of the quantum state of

motion312

1.Reconstruction of the number-state density

matrix313

2.Reconstruction of s-parametrized

quasiprobability distributions313

3.Experimental state reconstruction314 VII.Quantum Decoherence in the Motion of a Single

Atom315

A.Decoherence background316

B.Decoherence reservoirs316

1.High-temperature amplitude reservoir316

2.Zero-temperature amplitude reservoir318

3.High-temperature phase reservoir319

C.Ambient decoherence in ion traps320 VIII.Conclusions320 Acknowledgments320

REVIEWS OF MODERN PHYSICS,VOLUME75,JANUARY2003

0034-6861/2003/75(1)/281(44)/$35.00©2003The American Physical Society

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