Strain Tuning of Individual Atomic Tunneling Systems Detected by a Superconducting Qubit

Grabovskij, Grigorij J.; Peichl, Torben; Lisenfeld, Jürgen; Weiß, G.; Ustinov, A. V.

doi:10.1126/science.1226487

Cited by 136 publications

(167 citation statements)

References 30 publications

Supporting

Mentioning

146

Contrasting

Order By: Relevance

“…It is possible that the surface TLFs have a larger ∆ max than those in the niobium-sapphire interface, but this should appear within the loss tangent measurements. Instead we suspect the resonator couples to a coherent bath of TLFs, which are themselves affected by the incoherent action of other TLFs as was recently suggested by Faoro and Ioffe [3] and observed by Grabovskij [2]. The action of 'slow' fluctuators limits the RMS deviation of the resonance frequency over large time scales ∼1 second which leads to the observed flicker frequency noise.…”

Section: (See Supplemental Materials At [Url] For [Spectral Analysis])mentioning

confidence: 91%

“…In particular the flicker level is observed to decrease with increasing temperature and increasing microwave drive. These slow processes are described in theory [4] [3] and have been shown to affect qubits [2] and are expected to affect other superconducting or charge sensitive devices such as kinetic inductance detectors.…”

Section: (See Supplemental Materials At [Url] For [Spectral Analysis])mentioning

confidence: 99%

“…Recently, their effects were indirectly observed in superconducting qubits [2] with supporting theoretical work [3] linking them to the presence of two level fluctuators (TLFs) [4]. We present measurements directly probing these slow noise processes in superconducting resonators using a high bandwidth feedback technique with Hz level resolution [5].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Slow noise processes in superconducting resonators

et al. 2013

View full text Add to dashboard Cite

Slow noise processes, with characteristic timescales ∼1s, have been studied in planar superconducting resonators. A frequency locked loop is employed to track deviations of the resonator centre frequency with high precision and bandwidth. Comparative measurements are made in varying microwave drive, temperature and between bare resonators and those with an additional dielectric layer. All resonators are found to exhibit flicker frequency noise which increases with decreasing microwave drive. We also show that an increase in temperature results in a saturation of flicker noise in resonators with an additional dielectric layer, while bare resonators stop exhibiting flicker noise instead showing a random frequency walk process.Slow fluctuations in charge sensitive devices have been frequently examined over the past few decades [1]. Recently, their effects were indirectly observed in superconducting qubits [2] with supporting theoretical work [3] linking them to the presence of two level fluctuators (TLFs) [4]. We present measurements directly probing these slow noise processes in superconducting resonators using a high bandwidth feedback technique with Hz level resolution [5]. Feedback maintains a lock to the resonator centre frequency indefinitely, providing a direct measure of the nature of slow fluctuations and their behavior in varying temperature, microwave drive and TLF density. Theoretical work [3] suggests that 'slow' fluctuators can have a profound -but indirect-effect on the noise and losses in superconducting devices operating at microwave frequencies such as qubits. In simplified terms the model considers two distinct ensembles of TLFs: a coherent population that couples directly to the device, and a 'slow' population which perturbs the coherent TLFs, by changing the tunnel splitting. Hence, whereas the coherent processes between the two energy levels are expected to have short time constants, they are in turn effectively being modulated by processes that can have time constants of the order of seconds or even hours.Motivated by QIP applications, recent studies on superconducting resonators have focused heavily on sources of dissipation. Measurements have evaluated the effects of magnetic fields[6] and vortex motion [7]. The remaining dissipation channel is usually attributed to the presence of TLFs. The exact nature of TLFs remains contentious, but a variety of experiments have studied their effects [8][9][10][11][12] and recent models evaluated the contributions of TLFs in varying locations [13].In this letter we study slow noise processes in low loss niobium (Nb) on sapphire resonators [11]. Resonators are by their very nature sensitive probes: any change in the environment will produce a change in the centre frequency ν 0 of the resonator; making them ideal devices for studying noise. However, measuring this noise can be difficult due to the extrinsic low frequency noise present in equipment such as amplifiers and mixers [14]. Here we overcome this problem by using a high-bandwidth measurement metho...

show abstract

Section: (See Supplemental Materials At [Url] For [Spectral Analysis])mentioning

confidence: 91%

Section: (See Supplemental Materials At [Url] For [Spectral Analysis])mentioning

confidence: 99%

See 1 more Smart Citation

Slow noise processes in superconducting resonators

et al. 2013

View full text Add to dashboard Cite

show abstract

“…Such transition can be demonstrated by coupling mechanical resonators to other quantum objects [3], including superconducting qubit circuits [4][5][6][7][8][9][10][11][12][13][14], transmission line resonators [15][16][17][18][19], optical cavities [20][21][22][23], nitrogenvacancy (NV) centers [24][25][26], electron spin [27], and twolevel defects [28,29]. For example, the quantization of mechanical oscillations can be demonstrated by phonon blockade [12], which can be measured by a cavity field [30].…”

Section: Introductionmentioning

confidence: 99%

Optomechanical analog of two-color electromagnetically induced transparency: Photon transmission through an optomechanical device with a two-level system

et al. 2014

View full text Add to dashboard Cite

Some optomechanical systems can be transparent to a probe field when a strong driving field is applied. These systems can provide an optomechanical analogue of electromagnetically-induced transparency (EIT). We study the transmission of a probe field through a hybrid optomechanical system consisting of a cavity and a mechanical resonator with a two-level system (qubit). The qubit might be an intrinsic defect inside the mechanical resonator, a superconducting artificial atom, or another two-level system. The mechanical resonator is coupled to the cavity field via radiation pressure and to the qubit via the Jaynes-Cummings interaction. We find that the dressed twolevel system and mechanical phonon can form two sets of three-level systems. Thus, there are two transparency windows in the discussed system. We interpret this effect as an optomechanical analog of two-color EIT (or double-EIT). We demonstrate how to switch between one and two EIT windows by changing the transition frequency of the qubit. We show that the absorption and dispersion of the system are mainly affected by the qubit-phonon coupling strength and the transition frequency of the qubit.

show abstract

“…6,16,17 In recent experiments on the mechanism and interaction of TLSs in superconducting qubits, TLSs are detected through the standard energy spectroscopy measurement. 20,21 With this traditional method, the coupling between a TLS and a qubit results in an anti-crossing (or energy level splitting) on spectroscopy. 5,6,18,19,22,23 However, the visibility of the anti-crossing depends on the width of the resonant peak as well as the measurement resolution.…”

mentioning

confidence: 99%

Rapid characterization of microscopic two-level systems using Landau-Zener transitions in a superconducting qubit

Tan

et al. 2015

Applied Physics Letters

View full text Add to dashboard Cite

We demonstrate a fast method to detect microscopic two-level systems in a superconducting phase qubit. By monitoring the population leak after sweeping the qubit bias flux, we are able to measure the two-level systems that are coupled with the qubit. Compared with the traditional method that detects two-level systems by energy spectroscopy, our method is faster and more sensitive. This method supplies a useful tool to investigate two-level systems in solid-state qubits.

show abstract

Strain Tuning of Individual Atomic Tunneling Systems Detected by a Superconducting Qubit

Cited by 136 publications

References 30 publications

Slow noise processes in superconducting resonators

Slow noise processes in superconducting resonators

Optomechanical analog of two-color electromagnetically induced transparency: Photon transmission through an optomechanical device with a two-level system

Rapid characterization of microscopic two-level systems using Landau-Zener transitions in a superconducting qubit

Contact Info

Product

Resources

About