Atom Chips

Atom Chips......Page 1
Contents......Page 7
Preface......Page 17
List of Contributors......Page 19
Part One Fundamentals......Page 23
1.1 Introduction......Page 25
1.2 Historical Background......Page 26
1.3.1 Basic Principles......Page 29
1.3.2 Experimental Realization of Magnetic Mirrors......Page 31
1.4.1 Background......Page 35
1.4.2 BEC on a Magnetic Film Atom Chip......Page 36
1.4.3 Spatially Resolved RF Spectroscopyto Probe Magnetic Film Topology......Page 38
1.4.4 Adiabatic Splitting of a BEC for Asymmetric Potential Sensing......Page 41
1.4.5 Spatially Inhomogeneous Phase Evolutionof a Two-Component BEC......Page 43
1.4.6 BEC on Other Permanent-Magnet Atom Chips......Page 44
1.5.1 Background......Page 45
1.5.2 Basic Principles......Page 46
1.6 Summary and Conclusions......Page 50
References......Page 51
2.1 Introduction......Page 55
2.2 Overview of Trapping Techniques......Page 56
2.3.1 Magnetic Interaction......Page 57
2.3.2 Stability against Spin-Flip Losses......Page 58
2.3.4 Ioffe–Pritchard Traps......Page 59
2.3.5 Some General Properties of Magnetic Traps......Page 60
2.4.1 Conductor Elements and Multipoles......Page 61
2.4.2 Wire Guide......Page 62
2.4.3 Conductor Cross (“Dimple” Trap)......Page 63
2.4.4 “H”, “Z”, and “U” Traps......Page 65
2.4.5 Finite Wire Dimensions......Page 66
2.4.6 Maximum Confinement......Page 68
2.4.7 Combining Elements: Arrays, Conveyors and Others......Page 69
2.5.1 Effect of Wire Roughness......Page 70
2.5.2 Heat Transport and Maximum Current......Page 71
2.6.1 Mirror-MOT......Page 73
2.6.3 “Mode Matching”......Page 74
2.7.1 Traditional Cell......Page 75
2.7.2 Compact Cell with Atom Chip Wall......Page 77
2.8 Conclusion and Outlook......Page 79
References......Page 80
3.1 Introduction......Page 83
3.2 Fabrication Challenges......Page 84
3.3 The Substrate......Page 85
3.4.1 Optical Lithography......Page 87
3.4.2 Electron-Beam Lithography......Page 89
3.5.1 Deposition and Etching......Page 90
3.5.2 Effects of Roughness and Homogeneity of the Fabricated Structures......Page 96
3.5.3 Special Metals......Page 98
3.5.4 Permanent Magnets......Page 102
3.5.5 Metal Outlook......Page 104
3.6.1 Planarization and Insulation......Page 107
3.6.2 On-Chip Mirrors......Page 109
3.6.3 Multi-Layer Chips......Page 110
3.7 Current Densities and Tests......Page 113
3.8.1 Fiber-Based Integrated Optics......Page 115
3.8.2 Microlens and Cylindrical Lens......Page 119
3.8.3 Microdisks and Microtoroids......Page 120
3.8.4 Mounted and Fully Integrated Fabry–Pérots......Page 121
3.8.5 Planar Optics......Page 123
3.8.6 Photonics Outlook......Page 124
3.9 Chip Dicing, Mounting, and Bonding......Page 126
3.10 Further Integration and Portability......Page 128
3.11 Conclusion and Outlook......Page 131
References......Page 132
Part Two Ultracold Atoms near a Surface......Page 141
4.1 Introduction......Page 143
4.2 Principles of QED in Dielectrics......Page 145
4.3.1 Spin Flips near a Dielectric or Metallic Surface......Page 148
4.3.2 Spin Flips near a Superconductor......Page 152
4.3.3 Transverse Spin Relaxation......Page 154
4.3.4 Heating......Page 155
4.3.5 Electric Dipole Coupling of Molecules to a Surface......Page 156
4.4 Casimir–Polder Forces......Page 160
4.5 Closing Remarks......Page 166
References......Page 167
5.1 Qualitative Overview......Page 169
5.1.1 Electromagnetic Dipole Moments......Page 170
5.1.2 Electromagnetic Field Strengths......Page 171
5.1.3 Digression: Surface Green Functions......Page 173
5.2.1 Charges and Permanent Dipoles......Page 175
5.2.2 Van der Waals Potential......Page 176
5.2.3 Casimir–Polder Potential......Page 177
5.2.4 Recent Developments......Page 178
5.3 Surface-Induced Atomic Transitions......Page 179
5.3.1 Visible Frequencies: Spontaneous Emission......Page 180
5.3.2 Thermal Frequencies: Spin-Flips......Page 181
5.3.3 Trap Heating......Page 183
5.3.4 Atom Chips and Decoherence......Page 184
5.4 Perspectives......Page 187
References......Page 188
Part Three Coherence on Atom Chips......Page 193
6.1 Introduction......Page 195
6.2.1 The BEC Apparatus......Page 196
6.2.2 The Magnetic Lattice Chip......Page 199
6.3.1 Infinite Lattice......Page 200
6.3.2 Finite Size Effects......Page 203
6.3.3 The Double Meander Potential......Page 204
6.4.1 Diffraction Scheme......Page 206
6.4.2 Theoretical Model for the Interaction......Page 207
6.4.3 Diffraction in the Raman–Nath Regime......Page 211
6.4.4 Evolution of the Wave Function after the Lattice Interaction......Page 212
6.5 Ballistic Expansion and Phase Imprinting......Page 216
6.6 Experimental Results......Page 217
6.7.1 Modeling BEC Surface Diffraction......Page 224
6.7.2 Density Profile Dynamics......Page 225
6.7.3 Phase Modification by Inter-Atomic Interactions......Page 226
6.7.4 Comparison of the Interacting Theory with Experiment......Page 227
6.7.5 Locating the Low-Interaction Regime......Page 228
6.8 Conclusion......Page 229
References......Page 230
7.1 Introduction......Page 233
7.2.1 Transverse Splitting......Page 235
7.2.2 Longitudinal Splitting......Page 243
7.2.3 Electrostatic Splitter......Page 244
7.3 Atom Chip BEC Splitters Based on Dressed Adiabatic Potentials......Page 246
7.3.1 Dressed Adiabatic State Potentials......Page 247
7.3.2 A BEC Splitter Based on Dressed Adiabatic State Potentials......Page 250
7.3.3 Beyond the Rotating-Wave Approximation......Page 252
7.3.4 Implementation on an Atom Chip......Page 253
7.3.5 Advantages of RF-Induced Splitters over Static Splitters......Page 254
7.4.1 Theoretical Aspects......Page 256
7.4.2 Experimental Realizations......Page 260
7.5 Interferometry with 1D quasi condensates......Page 268
7.5.1 Coherently Split 1D BECs: Coherence Dynamics......Page 269
7.5.2 Independent 1D BECs: Noise Statistics of Interference Amplitude......Page 274
7.6 Summary and Outlook......Page 279
References......Page 281
8.2 Atomic-Fountain versus Trapped-Atom Clocks......Page 287
8.4 Clocks with Magnetically Trapped Atoms:Fundamental Limits to Performance......Page 289
8.5 Clocks with Magnetically Trapped Atoms:Experimental Demonstrations......Page 293
8.6 Readout in Trapped-Atom Clocks......Page 296
8.7 Spin Squeezing......Page 299
References......Page 300
9.1 Introduction......Page 305
9.2 Ingredients for QIP with Atom Chips......Page 306
9.3 Qubit States with Long Coherence Lifetime......Page 307
9.4 Qubit Rotations (Single-Qubit Gates)......Page 310
9.5 Single-Qubit Readout (Single-Atom Detection)......Page 312
9.7 Conditional Dynamics (Two-Qubit Gates)......Page 313
9.7.1 Internal-State Qubits and Collisional Interactions......Page 314
9.7.2 Motional-State Qubits and Collisional Interactions......Page 320
9.7.4 Cavity-QED-Based Schemes......Page 322
9.7.5 Quantum Gate Schemes that Can Be Adapted from Other Contexts......Page 323
9.8.1 Hybrid Approaches to Entanglement Generation......Page 325
9.8.3 Quantum Information Technology for Precision Measurementand Other Applications......Page 326
References......Page 327
Part Four New Directions......Page 331
10.1 Introduction......Page 333
10.2.1 Experimental Considerations......Page 334
10.2.2 Trapping and Cooling: First Results......Page 338
10.3.1 Probing the Superconducting Film Current Distribution......Page 341
10.3.2 Integration of Atom Chips with Superconducting Circuit Elements......Page 343
10.3.3 Atom Chips for Circular Rydberg States......Page 347
10.4 Conclusion......Page 350
References......Page 351
11.1 Introduction......Page 353
11.2 Regimes of One-Dimensional Gases......Page 354
11.2.1 Strongly versus Weakly Interacting Regimes......Page 356
11.2.2 Nearly Ideal Gas Regime......Page 357
11.2.3 Quasi-Condensate Regime......Page 360
11.2.4 Exact Thermodynamics......Page 364
11.3.1 Transverse Trapping and Nearly 1D Bose Gases......Page 367
11.3.3 Longitudinal Trapping......Page 369
11.3.4 3D Physics versus 1D Physics......Page 371
11.4 Experiments......Page 373
11.4.1 Failure of the Hartree–Fock Model......Page 374
11.4.2 Yang–Yang Analysis......Page 375
11.4.3 Measurements of Density Fluctuations......Page 377
11.5 Conclusion......Page 381
References......Page 382
12.1 Introduction......Page 387
12.2.1 Thermodynamics......Page 388
12.2.2 Density Distribution......Page 390
12.2.3 Crossover to Fermi Degeneracy......Page 392
12.3 The Atom Chip......Page 393
12.3.2 Electrical and Mechanical Connections......Page 394
12.4 Loading the Microtrap......Page 395
12.4.2 Loading Bosons and Fermions onto the Atom Chip......Page 396
12.4.3 Effective Trap Volume......Page 397
12.4.4 A Full Tank of Atoms: Maximum Trapped Atom Number......Page 398
12.5 Rapid Sympathetic Cooling of a K-Rb Mixture......Page 399
12.5.1 Forced Sympathetic RF Evaporation......Page 400
12.5.2 K-Rb Cross-Thermalization......Page 401
12.5.4 Required Temperature......Page 402
12.5.5 Experimental Signatures of Fermi Degeneracy......Page 403
12.6 Species-Selective RF Manipulation......Page 404
12.6.1 Sympathetic RF Evaporation......Page 405
12.6.2 Species-Selective Double Wells......Page 407
12.7 Fermions in an Optical Dipole Trap near an Atom Chip......Page 409
12.7.2 Loading the Optical Trap......Page 410
12.7.3 Microwave and RF Manipulation......Page 411
12.8 Discussion and Future Outlook......Page 412
References......Page 413
13.1 Introduction......Page 417
13.2.1 Motion of Ions in a Spatially Inhomogeneous RF Field......Page 418
13.2.2 Electrode Geometries for Linear Quadrupole Traps......Page 420
13.3.1 Doppler Cooling......Page 421
13.3.2 Micromotion......Page 423
13.3.3 Exposed Dielectric......Page 424
13.3.4 Loading Ions......Page 425
13.3.5 Electrical Connections......Page 426
13.3.6 Motional Heating......Page 427
13.4 Measuring Heating Rates......Page 428
13.5 Multiple Trapping Zones......Page 429
13.6.1 Modeling 3D Geometries......Page 430
13.6.2 Analytic Solutions for Surface-Electrode Traps......Page 431
13.7 Trap Examples......Page 433
13.8 Future......Page 437
References......Page 439
Index......Page 443