Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1407.3229 · Physical Review A

Emulating quantum state transfer through a spin-1 chain on a one-dimensional lattice of superconducting qutrits

Joydip Ghosh

Published Dec 10, 2014• 7 citations
arXivHTMLPDF

Abstract

Spin-1 systems, in comparison to spin-$\frac{1}{2}$ systems, offer a better security for encoding and transferring quantum information, primarily due to their larger Hilbert spaces. Superconducting artificial atoms possess multiple energy levels, thereby being capable of emulating higher-spin systems. Here I consider a one-dimensional lattice of nearest-neighbor-coupled superconducting transmon systems, and devise a scheme to transfer an arbitrary qutrit state (a state encoded in a three-level quantum system) across the chain. I assume adjustable couplings between adjacent transmons, derive an analytic constraint for the control pulse, and show how to satisfy the constraint to achieve a high-fidelity state transfer under current experimental conditions. My protocol thus enables enhanced quantum communication and information processing with promising superconducting qutrits.

DOI
10.1103/physreva.90.062318

Related papers

Transferring arbitrary d-dimensional quantum states of a superconducting transmon qudit in circuit QED

Tong Liu, Qi-Ping Su, Jin-Hu Yang +4 more

A qudit (d-level quantum system) has a large Hilbert space and thus can be used to achieve many quantum information and communication tasks. Here, we propose a method to transfer arbitrary d-dimensional quantum states (known or unknown) between two superconducting transmon qudits coupled to a single cavity. The state transfer can be performed by employing resonant interactions only. In addition, quantum states can be deterministically transferred without measurement. Numerical simulations show that high-fidelity transfer of quantum states between two superconducting transmon qudits (d ≤ 5) is feasible with current circuit QED technology. This proposal is quite general and can be applied to accomplish the same task with natural or artificial atoms of a ladder-type level structure coupled to a cavity or resonator.

arXiv:1610.05995•Scientific Reports•Jul 26, 2017•17 citations

A superconducting qutrit link beyond the qubit limit

Xiang Li, Zheng-Yang Mei, Yang He +7 more

Superconducting microwave links have enabled deterministic state transfer and remote entanglement between qubits, but deterministic links have so far operated with an effectively two-dimensional transmitted Hilbert space. Here we demonstrate a superconducting qutrit link between two independently packaged nodes connected by a microwave channel. Each node combines a transmon qutrit, a transmission resonator, and a tunable Purcell-filter interface, allowing the two remote microwave-photon interfaces to be matched in both frequency and bandwidth. We implement two transition-selective photon-mediated operations that transfer the $|e\rangle$ and $|f\rangle$ qutrit components in distinct temporal modes of the same channel. We tomographically characterize arbitrary qutrit-state transfer, obtaining a mean transferred-state fidelity of 83.68% and a qutrit process fidelity of 77.12%, exceeding both the classical qutrit-transfer benchmark and the best possible average fidelity of an effective qubit channel used to transmit an arbitrary qutrit. Using partial-transfer operations, we reconstruct a remote two-qutrit state with negativity 0.730, a tomography-inferred dense-coding capacity of 2.273 bits, and a tomography-inferred Collins-Gisin-Linden-Massar-Popescu (CGLMP) parameter $I_3=2.332$, all beyond the corresponding qubit or local bounds. These results demonstrate a superconducting microwave link that uses the native three-level structure of transmons as a genuine high-dimensional communication resource.

quant-pharXiv:2606.29475•Jun 30, 2026•0 citations

Efficient transfer of an arbitrary qutrit state in circuit quantum electrodynamics

Tong Liu, Shao-Jie Xiong, Xiao-Zhi Cao +2 more

Compared with a qubit, a qutrit (i.e., three-level quantum system) has a larger Hilbert space and thus can be used to encode more information in quantum information processing and communication. Here, we propose a method to transfer an arbitrary quantum state between two flux qutrits coupled to two resonators. This scheme is simple because it only requires two basic operations. The state-transfer operation can be performed fast because only resonant interactions are used. Numerical simulations show that the high-fidelity transfer of quantum states between the two qutrits is feasible with current circuit-QED technology. This scheme is quite general and can be applied to accomplish the same task for other solid-state qutrits coupled to resonators.

arXiv:1610.02679•Optics Letters•Nov 23, 2015•19 citations

Implementation of a hybrid controlled-SUM gate with one superconducting qutrit simultaneously controlling multiple-target cat-state qutrits

Dong-Xuan Zhang, Jia-Heng Ni, Yu Zhang +4 more

Compared to a qubit, a qutrit (a three-level or three-state quantum system) possesses a larger Hilbert space to process and store quantum information. On the other hand, large-scale qutrit-based hybrid quantum computing usually requires performing hybrid multi-qutrit quantum gates with diverse qutrits, different in their nature or in their encoding format. In this work, we consider two types of qutrits, i.e., superconducting (SC) qutrits and cat-state qutrits. We propose to implement a hybrid controlled-SUM gate with one SC qutrit simultaneously controlling multiple-target cat-state qutrits. The gate is implemented in a circuit-QED system, which is composed of an SC ququart and multiple microwave cavities. The SC ququart here refers to a four-level quantum system, with the three lowest levels forming a qutrit and an auxiliary higher energy level utilized for the coherent state manipulation. The gate implementation does not require applying a classical pulse. Because the auxiliary higher energy level of the SC ququart is only virtually excited during the gate operation, decoherence from this level is greatly suppressed. The gate is deterministic, as it requires no measurement of the cavity or SC ququart states. Moreover, the gate operational time is independent of the number of qutrits, thus it does not increase with the number of qutrits. As an application of this gate, we further discuss the generation of a hybrid maximally entangled state of one SC qutrit and multiple cat-state qutrits. We also numerically analyze the experimental feasibility of creating the hybrid entangled state of one SC qutrit and two cat-state qutrits in a circuit QED system. This proposal may be extended to accomplish the same task in other physical systems, such as a four-level artificial atom (e.g., a quantum dot, an NV center, a magnon, etc.) coupled to multiple optical or microwave cavities.

Chinese Journal of Physics•Nov 29, 2025•2 citations

Control and Tomography of a Three Level Superconducting Artificial Atom

R. Bianchetti, Stefan Filipp, Matthias Baur +6 more

A number of superconducting qubits, such as the transmon or the phase qubit, have an energy level structure with small anharmonicity. This allows for convenient access of higher excited states with similar frequencies. However, special care has to be taken to avoid unwanted higher-level populations when using short control pulses. Here we demonstrate the preparation of arbitrary three level superposition states using optimal control techniques in a transmon. Performing dispersive readout, we extract the populations of all three levels of the qutrit and study the coherence of its excited states. Finally we demonstrate full quantum state tomography of the prepared qutrit states and evaluate the fidelities of a set of states, finding on average 95%.

arXiv:1004.5504•Physical Review Letters•Nov 24, 2010•164 citations

Realization of the iSWAP-like gate among the superconducting qutrits

Peng Xu, Ran Zhang, Shengmei Zhao

High-dimensional quantum systems, such as qutrits (quantum three-level systems), have multiple accessible energy levels beyond the two-level qubits. Therefore, qutrits can offer a larger state space to improve the efficiency of quantum computation. Here, we demonstrate a high-fidelity iSWAP-like gate operation on a frequency-tunable superconducting qutrits system. The superconducting quantum system consists of two qutrits that are coupled via a resonator with fixed qutrit-resonator coupling strengths. Through designing the frequency pulse profile and optimizing the parameter values, the gate error can be suppressed below 1.5 × 10−3. To bear out the feasibility of the proposal, we have conducted our study with experimentally accessible parameters. As the resonator can mediate the interaction between the irrelevant qutrits, the presented approach can also be used to couple multiple qutrits together, providing a good platform for quantum information processing.

Chinese Physics B•Aug 16, 2022•1 citation
Spin-1 systems, in comparison to spin-12\frac{1}{2}21​ systems, offer a better security for encoding and transferring quantum information, primarily due to their larger Hilbert spaces. Superconducting artificial atoms possess multiple energy levels, thereby being capable of emulating higher-spin systems. Here I consider a one-dimensional lattice of nearest-neighbor-coupled superconducting transmon systems, and devise a scheme to transfer an arbitrary qutrit state (a state encoded in a three-level quantum system) across the chain. I assume adjustable couplings between adjacent transmons, derive an analytic constraint for the control pulse, and show how to satisfy the constraint to achieve a high-fidelity state transfer under current experimental conditions. My protocol thus enables enhanced quantum communication and information processing with promising superconducting qutrits.
A qudit (d-level quantum system) has a large Hilbert space and thus can be used to achieve many quantum information and communication tasks. Here, we propose a method to transfer arbitrary d-dimensional quantum states (known or unknown) between two superconducting transmon qudits coupled to a single cavity. The state transfer can be performed by employing resonant interactions only. In addition, quantum states can be deterministically transferred without measurement. Numerical simulations show that high-fidelity transfer of quantum states between two superconducting transmon qudits (d ≤ 5) is feasible with current circuit QED technology. This proposal is quite general and can be applied to accomplish the same task with natural or artificial atoms of a ladder-type level structure coupled to a cavity or resonator.
Superconducting microwave links have enabled deterministic state transfer and remote entanglement between qubits, but deterministic links have so far operated with an effectively two-dimensional transmitted Hilbert space. Here we demonstrate a superconducting qutrit link between two independently packaged nodes connected by a microwave channel. Each node combines a transmon qutrit, a transmission resonator, and a tunable Purcell-filter interface, allowing the two remote microwave-photon interfaces to be matched in both frequency and bandwidth. We implement two transition-selective photon-mediated operations that transfer the ∣e⟩|e\rangle∣e⟩ and ∣f⟩|f\rangle∣f⟩ qutrit components in distinct temporal modes of the same channel. We tomographically characterize arbitrary qutrit-state transfer, obtaining a mean transferred-state fidelity of 83.68% and a qutrit process fidelity of 77.12%, exceeding both the classical qutrit-transfer benchmark and the best possible average fidelity of an effective qubit channel used to transmit an arbitrary qutrit. Using partial-transfer operations, we reconstruct a remote two-qutrit state with negativity 0.730, a tomography-inferred dense-coding capacity of 2.273 bits, and a tomography-inferred Collins-Gisin-Linden-Massar-Popescu (CGLMP) parameter I3=2.332I_3=2.332I3​=2.332, all beyond the corresponding qubit or local bounds. These results demonstrate a superconducting microwave link that uses the native three-level structure of transmons as a genuine high-dimensional communication resource.
Compared with a qubit, a qutrit (i.e., three-level quantum system) has a larger Hilbert space and thus can be used to encode more information in quantum information processing and communication. Here, we propose a method to transfer an arbitrary quantum state between two flux qutrits coupled to two resonators. This scheme is simple because it only requires two basic operations. The state-transfer operation can be performed fast because only resonant interactions are used. Numerical simulations show that the high-fidelity transfer of quantum states between the two qutrits is feasible with current circuit-QED technology. This scheme is quite general and can be applied to accomplish the same task for other solid-state qutrits coupled to resonators.
Compared to a qubit, a qutrit (a three-level or three-state quantum system) possesses a larger Hilbert space to process and store quantum information. On the other hand, large-scale qutrit-based hybrid quantum computing usually requires performing hybrid multi-qutrit quantum gates with diverse qutrits, different in their nature or in their encoding format. In this work, we consider two types of qutrits, i.e., superconducting (SC) qutrits and cat-state qutrits. We propose to implement a hybrid controlled-SUM gate with one SC qutrit simultaneously controlling multiple-target cat-state qutrits. The gate is implemented in a circuit-QED system, which is composed of an SC ququart and multiple microwave cavities. The SC ququart here refers to a four-level quantum system, with the three lowest levels forming a qutrit and an auxiliary higher energy level utilized for the coherent state manipulation. The gate implementation does not require applying a classical pulse. Because the auxiliary higher energy level of the SC ququart is only virtually excited during the gate operation, decoherence from this level is greatly suppressed. The gate is deterministic, as it requires no measurement of the cavity or SC ququart states. Moreover, the gate operational time is independent of the number of qutrits, thus it does not increase with the number of qutrits. As an application of this gate, we further discuss the generation of a hybrid maximally entangled state of one SC qutrit and multiple cat-state qutrits. We also numerically analyze the experimental feasibility of creating the hybrid entangled state of one SC qutrit and two cat-state qutrits in a circuit QED system. This proposal may be extended to accomplish the same task in other physical systems, such as a four-level artificial atom (e.g., a quantum dot, an NV center, a magnon, etc.) coupled to multiple optical or microwave cavities.
A number of superconducting qubits, such as the transmon or the phase qubit, have an energy level structure with small anharmonicity. This allows for convenient access of higher excited states with similar frequencies. However, special care has to be taken to avoid unwanted higher-level populations when using short control pulses. Here we demonstrate the preparation of arbitrary three level superposition states using optimal control techniques in a transmon. Performing dispersive readout, we extract the populations of all three levels of the qutrit and study the coherence of its excited states. Finally we demonstrate full quantum state tomography of the prepared qutrit states and evaluate the fidelities of a set of states, finding on average 95%.
High-dimensional quantum systems, such as qutrits (quantum three-level systems), have multiple accessible energy levels beyond the two-level qubits. Therefore, qutrits can offer a larger state space to improve the efficiency of quantum computation. Here, we demonstrate a high-fidelity iSWAP-like gate operation on a frequency-tunable superconducting qutrits system. The superconducting quantum system consists of two qutrits that are coupled via a resonator with fixed qutrit-resonator coupling strengths. Through designing the frequency pulse profile and optimizing the parameter values, the gate error can be suppressed below 1.5 × 10−3. To bear out the feasibility of the proposal, we have conducted our study with experimentally accessible parameters. As the resonator can mediate the interaction between the irrelevant qutrits, the presented approach can also be used to couple multiple qutrits together, providing a good platform for quantum information processing.