High-fidelity heralded quantum state preparation and measurement

• URL: http://arxiv.org/abs/2409.05805v1
• Date: Mon, 9 Sep 2024 17:11:44 GMT
• Title: High-fidelity heralded quantum state preparation and measurement
• Authors: A. S. Sotirova, J. D. Leppard, A. Vazquez-Brennan, S. M. Decoppet, F. Pokorny, M. Malinowski, C. J. Ballance,
• Abstract summary: We present a novel protocol for high-fidelity qubit state preparation and measurement (SPAM) It combines standard SPAM methods with a series of in-sequence measurements to detect and remove errors. We demonstrate the use of the protocol for three different qubit encodings in a single trapped $137mathrmBa+$ ion.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We present a novel protocol for high-fidelity qubit state preparation and measurement (SPAM) that combines standard SPAM methods with a series of in-sequence measurements to detect and remove errors. The protocol can be applied in any quantum system with a long-lived (metastable) level and a means to detect population outside of this level without coupling to it. We demonstrate the use of the protocol for three different qubit encodings in a single trapped $^{137}\mathrm{Ba}^+$ ion. For all three, we achieve the lowest reported SPAM infidelities of $7(4) \times 10^{-6}$ (optical qubit), $5(4) \times 10^{-6}$ (metastable-level qubit), and $8(4) \times 10^{-6}$ (ground-level qubit).

Related papers

• Multi-qubit entanglement swapping with squeezed modes [37.69303106863453]
  We present a hybrid continuous variable-discrete variable entanglement swapping protocol. It is capable of producing a large number of high-fidelity Bell pairs per signal. The effectiveness of the protocol is determined by the squeezing strength.
  arXiv  Detail & Related papers  (2024-10-24T15:26:13Z)
• Quantum state testing with restricted measurements [30.641152457827527]
  We develop an information-theoretic framework that yields unified copy complexity lower bounds for restricted families of non-adaptive measurements. We demonstrate a separation between these two schemes, showing the power of randomized measurement schemes over fixed ones.
  arXiv  Detail & Related papers  (2024-08-30T17:48:00Z)
• An optimal tradeoff between entanglement and copy complexity for state tomography [24.737530909081915]
  We study tomography in the natural setting where one can make measurements of $t$ copies at a time. This is the first smooth entanglement-copy protocol known for any quantum learning task. A key insight is to use SchurilonWeyl sampling not to estimate the spectrum of $rho$, but to estimate the deviation of $rho$ from the maximally mixed state.
  arXiv  Detail & Related papers  (2024-02-26T07:18:57Z)
• The role of shared randomness in quantum state certification with unentangled measurements [36.19846254657676]
  We study quantum state certification using unentangled quantum measurements. $Theta(d2/varepsilon2)$ copies are necessary and sufficient for state certification. We develop a unified lower bound framework for both fixed and randomized measurements.
  arXiv  Detail & Related papers  (2024-01-17T23:44:52Z)
• Efficient State Preparation for Metrology and Quantum Error Correction with Global Control [0.0]
  We introduce a simple, experimentally realizable protocol that can prepare any specific superposition of permutationally invariant qubit states, also known as Dicke states. We demonstrate the utility of our protocol by numerically preparing several states with theoretical infidelities $1-mathcalF10-4$. We estimate that the protocol achieves fidelities $gtrsim 95%$ in the presence of typical experimental noise levels.
  arXiv  Detail & Related papers  (2023-12-08T14:28:34Z)
• A Race Track Trapped-Ion Quantum Processor [0.0]
  We describe and benchmark a new quantum charge-coupled device based on a linear trap with periodic boundary conditions. The system is initially operated with 32 qubits, but future upgrades will allow for more.
  arXiv  Detail & Related papers  (2023-05-05T20:07:37Z)
• Efficient Bipartite Entanglement Detection Scheme with a Quantum Adversarial Solver [89.80359585967642]
  Proposal reformulates the bipartite entanglement detection as a two-player zero-sum game completed by parameterized quantum circuits. We experimentally implement our protocol on a linear optical network and exhibit its effectiveness to accomplish the bipartite entanglement detection for 5-qubit quantum pure states and 2-qubit quantum mixed states.
  arXiv  Detail & Related papers  (2022-03-15T09:46:45Z)
• Improving resilience of the Quantum Gravity Induced Entanglement of Masses (QGEM) to decoherence using 3 superpositions [0.0]
  We introduce a third mass with an embedded qubit, so that there are now 3 qubits to witness the gravitationally generated entanglement. The entanglement can be detected experimentally for the 2-qubit setup if the decoherence rate $gamma$ is $gamma 0.11 $ Hz. We estimate that the 3-qubit setup would allow detecting the entanglement in the QGEM protocol at a $99.9%$ certainty with $O(104)-O(105)$ measurements.
  arXiv  Detail & Related papers  (2021-10-27T18:23:51Z)
• Weak dissipation for high fidelity qubit state preparation and measurement [0.0]
  We show a total qubit state preparation and measurement (SPAM) inaccuracy $epsilon_mathrmSPAM 1.7 times 10-4$ ($-38 mbox dB$) We show experimentally that full transfer would yield an inaccuracy less than $8.0 times 10-5$ ($-41 mbox dB$) Since this technique allows fluorescence collection for effectively unlimited periods, high fidelity qubit SPAM is achievable even with limited optical access and low quantum efficiency.
  arXiv  Detail & Related papers  (2021-08-26T22:28:01Z)
• Entanglement purification by counting and locating errors with entangling measurements [62.997667081978825]
  We consider entanglement purification protocols for multiple copies of qubit states. We use high-dimensional auxiliary entangled systems to learn about number and positions of errors in the noisy ensemble.
  arXiv  Detail & Related papers  (2020-11-13T19:02:33Z)
• Estimation of pure states using three measurement bases [0.0]
  We introduce a new method to estimate unknown pure $d$-dimensional quantum states using the probability distributions associated with only three measurement bases. The viability of the protocol is experimentally demonstrated using two different and complementary high-dimensional quantum information platforms.
  arXiv  Detail & Related papers  (2020-06-05T03:28:51Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.