Katz, N., Neeley, M., Ansmann, M., Bialczak, R. C., H<strong>of</strong>heinz, M., Lucero, E., O’Connell, A. D., Wang, H., Cleland, A. N., Martinis, J. M., and Korotkov, A. N., “Reversal <strong>of</strong> the Weak Measurement <strong>of</strong> a Quantum State in a Superconducting Phase Qubit”, Physical Review Letters (2008), 101:200401 Levy, A. R., Leonardi, R., Ansmann, M., Bersanelli, M., Childers, J., Cole, T. D., D’Arcangelo, O., Davis, G. V., Lubin, P. M., Marvil, J., Meinhold, P. R., Miller, G., O’Neill, H., Stavola, F., Stebor, N. C., Timbie, P. T., Van der Heide, M., Villa, F., Villela, T., Williams, B. D., Wuensche, C. A., “The White Mountain Polarimeter Telescope and an Upper Limit on Cosmic Microwave Background Polarization”, Astrophysical Journal Supplement Series (2008), 177:419-430 H<strong>of</strong>heinz, M., Weig, E. M., Ansmann, M., Bialczak, R. C., Lucero, E., Neeley, M., O’Connell, A. D., Wang, H., Martinis J. M., and Cleland, A. N., “Generation <strong>of</strong> Fock states in a superconducting quantum circuit”, Nature (2008), 454:310-314 Neeley, M., Ansmann, M., Bialczak, R. C., H<strong>of</strong>heinz, M., Katz, N., Lucero, E., O’Connell, A. D., Wang, H., Cleland, A. N., and Martinis J. M., “Process tomography <strong>of</strong> quantum memory in a Josephson-phase qubit coupled to a two-level state”, Nature <strong>Physics</strong> (2008), 4:523-526 Lucero, E., H<strong>of</strong>heinz, M., Ansmann, M., Bialczak, R. C., Katz, N., Neeley, M., OConnell, A.D., Wang, H., Cleland, A. N., and Martinis, J. M., “High-fidelity gates in a Josephson qubit”, Physical Review Letters (2008), 100:247001 Neeley, M., Ansmann, M., Bialczak, R. C., H<strong>of</strong>heinz, M., Katz, N., Lucero, E., OConnell, A. D., Wang, H., Cleland, A. N., and Martinis, J. M., “Transformed Dissipation in Superconducting Quantum Circuits”, Physical Review B (2008), 77:180508 O’Connell, A. D., Ansmann, M., Bialczak, R. C., H<strong>of</strong>heinz, M., Katz, N., Lucero, E., McKenney, C., Neeley, M., Wang, H., Weig, E. M., Cleland, A. N., and Martinis, J. M., “Microwave Dielectric Loss at Single Photon Energies and milliKelvin Temperatures”, Applied <strong>Physics</strong> Letters (2008), 92:112903 Bialczak, R. C., McDermott, R., Ansmann, M., H<strong>of</strong>heinz, M., Katz, N., Lucero, E., Neeley, M., O’Connell, A. D., Wang, H., Cleland, A. N., and Martinis, J. M., “1/f Flux Noise in Josephson Phase Qubits”, Physical Review Letters (2007), xii
99:187006 Lisenfeld, J., Lukashenko, A., Ansmann, M., Martinis, J. M., Ustinov, A. V., “Temperature dependence <strong>of</strong> coherent oscillations in Josephson phase qubits”, Physical Review Letters (2007), 99:170504 Steffen, M., Ansmann, M., Bialczak, R. C., Katz, N., Lucero, E., McDermott, R., Neeley, M., Weig, E. M., Cleland, A. N., and Martinis, J. M., “Measurement <strong>of</strong> the Entanglement <strong>of</strong> Two Superconducting Qubits via State Tomography”, Science (2006), 313:1423-1425 Steffen, M., Ansmann, M., McDermott, R., Katz, N., Bialczak, R. C., Lucero, E., Neeley, M., Weig, E. M., Cleland, A. N., and Martinis, J. M., “State tomography <strong>of</strong> capacitively shunted phase qubits with high fidelity”, Physical Review Letters (2006), 97:050502 Katz, N., Ansmann, M., Bialczak, R. C., Lucero, E., McDermott, R., Neeley, M., Steffen, M., Weig, E. M., Cleland, A. N., Martinis, J. M., and Korotkov, A. N., “Coherent state evolution in a superconducting qubit from partial-collapse measurement”, Science (2006), 312: 1498-1500 Marvil, J., Ansmann, M., Childers, J., Cole, T., Davis, G. V., Hadjiyska, E., Halevi, D., Heimberg, G., Kangas, M., Levy, A., Leonardi, R., Lubin, P., Meinhold, P., O’Neill, H., Parendo, S., Quetin, E., Stebor, N., Villela, T., Williams, B., Wuensche, C. A., and Yamaguchi, K., “An Astronomical Site Survey at the Barcr<strong>of</strong>t Facility <strong>of</strong> the White Mountain Research Station”, New Astronomy (2006), 11:218-225 Martinis, J. M., Cooper, K. B., McDermott, R., Steffen, M., Ansmann, M., Osborn, K., Cicak, K., Oh, S., Pappas, D. P., Simmonds, R.W., and Yu, C. C., “Decoherence in Josephson Qubits from Dielectric Loss”, Physical Review Letters (2005), 95:210503 Kangas, M. M., Ansmann, M., Copsey, K., Horgan, B., Leonardi, R., Lubin, P., Villela, T., “A 100-GHz high-gain tilted corrugated nonbonded platelet antenna”, IEEE Antennas and Wireless Propagation Letters (2005), 4:304-307 Kangas, M. M., Ansmann, M., Horgan, B., Lemaster, N., Leonardi, R., Levy, xiii
- Page 1: UNIVERSITY of CALIFORNIA Santa Barb
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- Page 11: Curriculum Vitæ Markus Ansmann Edu
- Page 15 and 16: Abstract Benchmarking the Supercond
- Page 17 and 18: Contents Contents List of Figures L
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- Page 23 and 24: 11.5 Analysis and Verification . .
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- Page 29 and 30: Chapter 1 Quantum Computation 1.1 M
- Page 31 and 32: for such problems include factoring
- Page 33 and 34: if present encrypted data will rema
- Page 35 and 36: In terms of quantum bits, this mean
- Page 37 and 38: 1.2.3 Implications - The EPR Parado
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- Page 49 and 50: • The circuit needs to be cooled
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- Page 55 and 56: Figure 2.4: Josephson Qubits: Sligh
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states in the qubit’s inductor, t
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at time t. r is not restricted to b
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3.1.2 Effects of a Time Dependent P
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In some cases, it is possible to so
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Figure 3.1: Examples of Numerical S
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• The energy difference between t
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like this: V = ( V (−1, −1), V
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Figure 3.2: Simulation of LC Oscill
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Table 3.1: Transition Matrix Elemen
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with ω mn = Em−En . Multiplying
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α, it can be ignored. Thus, the in
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e solved exactly: A(t + ∆t) = e
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qubits would be simulated using: A(
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This calculation assumes that the s
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Decoherence consists of two parts:
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Note the difference in signs of the
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Chapter 4 Designing the Phase Qubit
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mutual inductance between the qubit
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During the measurement, the | 1 〉
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the right impedance transformation
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excitations. Since these are a pote
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Figure 4.3: Squid I/V Traces - a) L
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Figure 4.5: Qubit Integrated Circui
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The geometry of the qubit junction
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squid loop. Thus, this tool can be
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now, amorphous silicon seems to pro
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Figure 5.1: L-Edit Mask Layout Tool
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Figure 5.2: Fabrication Building Bl
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Figure 5.3: Photolithography and Et
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times the removal can be a bit tric
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Figure 5.4: Clearing Vias from Nati
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5.6 Junction Layers 5.6.1 Oxidation
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top wiring layer to protect all low
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104
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6.1 Physical Quality Control during
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6.1.3 Atomic Force Microscopy To re
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Figure 6.1: 4-Wire Measurement - a)
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6.3 Quantum Measurements at 25 mK 6
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seems to be a box machined out of s
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Figure 6.2: Dilution Refrigerator W
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cessing data. This protects the vol
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6.3.9 Anritsu Microwave Source The
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122
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ment, the scalability requirements,
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people without any formal training
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7.2.4 Performance Last, but certain
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or a Client Module. Client Modules
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second Module talks to all these an
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puters to talk to each other. Usual
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7.3.4 Performance Addressing the Pe
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is designed such that the LabRAD Ma
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Table 7.3: LabRAD Type Annotations
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listed in Table 7.3. For transmissi
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Architecture to manage network conn
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Manager. In fact, in our lab, the o
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waiting for their completion. The C
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mentation of pipelining and certain
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Since the API guarantees that all R
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one microwave line for X/Y-rotation
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7.5.3 DC Rack Server The DC Rack Se
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data taking on the lab servers and
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keys and the ability to set Context
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a certain time. 7.5.9 Optimizer Cli
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ters read from different sub-direct
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efore the execution of the sequence
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can achieve very-close-to hardware
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type to provide a one-stop location
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172
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8.1 Squid I/V Response As explained
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a digital signal via the use of a c
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energy landscape (see Chapter 2.2.3
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Figure 8.3: Squid Steps Failure Mod
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At this point, the squid ramp can b
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starts to tunnel to the neighboring
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Figure 8.5: General Bias Sequence -
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Figure 8.7: Spectroscopy - a) Bias
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Figure 8.8: Rabi Oscillation - a) B
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ensemble with respect to each other
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Figure 8.10: T 1 - a) Bias sequence
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Figure 8.11: Ramsey - a) Bias seque
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phase shift into the middle of the
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photon excitation behaves similarly
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is desirable to modularize the cont
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sequence was run. This allows for t
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possible to read out all qubits cor
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simultaneous application of such me
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Figure 9.4: Capacitive Coupling Swa
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Figure 9.6: Capacitive Coupling Pha
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a phase difference of 0 ◦ rather
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Figure 9.7: Fine Spectroscopy of Re
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Figure 9.8: Swapping Photon into Re
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esonator. The latter calibration is
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Figure 9.11: Resonator T 1 - a) Seq
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224
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He does not throw dice” [Einstein
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(independent of which axis it is),
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of E xy is measured by expressing i
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For a measurement of two particles
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10.2.1 Photons The first and most n
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10.2.3 Ion and Photon In the attemp
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238
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11.1 State Preparation Since the ab
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Figure 11.1: Bell State Preparation
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Table 11.1: Entangled State Density
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Figure 11.2: Bell Measurements - a)
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11.2.3 Statistical Analysis For the
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11.3 Calibration The most difficult
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Table 11.4: Sequence Parameters - R
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ally determine an optimal value for
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ages are based on this method, incl
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equires to converge. Since the algo
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Table 11.7: Bell Violation Results
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Table 11.9: Error Budget - Capaciti
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Table 11.10: Bell Violation Results
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Bell inequality. To make this claim
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Table 11.12: Bell Violation Results
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11.5.2 Dependence of S on Sequence
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point where the measurement happens
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The second qubit is not driven and
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Figure 11.6: Resonator Coupled Samp
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From the resulting states, the 16 p
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Table 11.14: Error Budget - Resonat
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Table 11.15: Bell Violation Results
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sponding to a violation by 244.0σ.
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educe energy decay and dephasing an
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John F. Clauser, Michael A. Horne,
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J. Majer, J. M. Chow, J. M. Gambett
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Matthias Steffen, M. Ansmann, Rados