Radiofrequency to Microwave Coherent Manipulation of an Organometallic Electronic Spin Qubit Coupled to a Nuclear Qudit

Abstract

We report here a comprehensive characterization of a 3d organometallic complex, [V(Cp) 2 Cl 2 ] (Cp = cyclopentadienyl), which can be considered as a prototypical multilevel nuclear qudit (nuclear spin I = 7/2) hyperfine coupled to an electronic qubit (electronic spin S = 1/2). By combining complementary magnetic resonant techniques, such as pulsed electron paramagnetic resonance (EPR) and broadband nuclear magnetic resonance (NMR), we extensively characterize its Spin Hamiltonian parameters and its electronic and nuclear spin dynamics. Moreover, we demonstrate the possibility to manipulate the qubit–qudit multilevel structure by resonant microwave and radiofrequency pulses, driving coherent Rabi oscillations between targeted electronuclear states. The obtained results demonstrate that this simple complex is a promising candidate for quantum computing applications.

Controlled coherent dynamics of [VO(TPP)], a prototype molecular nuclear qudit with an electronic ancilla

“…The generality of this conclusion is further confirmed by the subsequent observation of a detectable effective quadrupole also in another coordination geometry of vanadium complex. 63 …”

Spin-Phonon Relaxation in Magnetic Molecules: Theory, Predictions and Insights

“…∂Q αq ∂Q βq 0 Qαq (t) Qβq (t) + ... , (28) where the naught symbol points to those quantities evaluated for the crystal geometry at zero-temperature, i.e. for the structure in its energy minimum.…”

“…Moreover, single molecules with long coherence times and addressable with single-qubit gates have already found application as building blocks of quantum architectures [16][17][18][19]. The implementation of two-qubit gates [20] and quantum algorithms using molecular spins have already been demonstrated [21], and the areas of quantum initialization and read-out [22], scaling of the number of qubits [23][24][25], and the interface of molecules with other quantum systems [26][27][28] are also rapidly progressing.…”

Molecular Spin Qubits Impregnated in a Hexagonal Self-Ordered Mesoporous Silica

“…The ∼15 MHz is the proton Larmor frequency and is enhanced when the Hartmann−Hahn condition is fulfilled. 48 This is quite common in molecular spin qubits, where protons are abundant, 49,50 and indicates a strong coherent coupling between the molecular electron spin and the proton bath. We cannot determine the origins of the frequencies of 22, 50, and 87 MHz, but it is quite probably related to the electron Larmor procession considering the large electron Larmor frequency of 28 GHz/T.…”