We present a novel approach to chiral discrimination using gate-based quantum processors, addressing a key challenge in adapting conventional control techniques using modern quantum computing. Schemes such as stimulated rapid adiabatic passage and shortcuts to adiabaticity have shown strong potential for enantiomer discrimination; however, their reliance on analog and continuous-time control makes them incompatible with digital gate-based quantum computing architectures. Here, we adapt these protocols for quantum computers by discretizing their Gaussian-shaped pulses through Trotterization. We simulate the chiral molecule 1,2-propanediol and experimentally validate this gate-based implementation on IBM quantum hardware. Our results demonstrate that this approach is a viable foundation for advancing chiral discrimination protocols, preparing the way for quantum-level manipulation of molecular chirality on accessible quantum architectures.
We present a novel approach to chiral discrimination using gate-based quantum processors, addressing a key challenge in adapting conventional control techniques using modern quantum computing. Schemes such as stimulated rapid adiabatic passage and shortcuts to adiabaticity have shown strong potential for enantiomer discrimination; however, their reliance on analog and continuous-time control makes them incompatible with digital gate-based quantum computing architectures. Here, we adapt these protocols for quantum computers by discretizing their Gaussian-shaped pulses through Trotterization. We simulate the chiral molecule 1,2-propanediol and experimentally validate this gate-based implementation on IBM quantum hardware. Our results demonstrate that this approach is a viable foundation for advancing chiral discrimination protocols, preparing the way for quantum-level manipulation of molecular chirality on accessible quantum architectures.
Quantum optical methods have great potential for highly efficient discrimination of chiral molecules. We propose quantum interference-based schemes of enantio-discrimination under microwave regime among molecular rotational states. The quantum interference between field-driven one- and two-photon transitions of two higher states is designed to be constructive for one enantiomer but destructive for the other, since a certain transition dipole moment can be set to change sign with enantiomers. Therefore, two enantiomers can evolve into entirely different states from the same ground state. Through strengthening the constructive interference, the quantum Zeno effect is found in one enantiomer and then its excitation is suppressed, which also enables the enantio-discrimination. We simulate the schemes for differentiating between S and R enantiomers of 1, 2-propanediol (C 3 H 8 O 2 ) molecules. With the analysis of the phase sensitivity to microwave fields and the effect of energy relaxations, the highly efficient enantio-discrimination of the 1, 2-propanediol molecules may be achieved.
We propose to discriminate chiral molecules by combining one- and two-photon processes in a closed-loop configuration. The one-photon-coupling intrinsic $\ensuremath{\pi}$-phase difference between two enantiomers leads to their different superposition states, which is then followed by a two-photon process through three-mode parallel paths (3MPPs), enabling the discrimination of enantiomers by inducing their entirely different population distributions. The 3MPPs are constructed by ``chosen paths,'' a method of shortcuts to adiabaticity, exhibiting a fast two-photon process. As an example, we propose to perform the scheme in 1,2-propanediol molecules, which show relatively robust and highly efficient results under considering the experimental issues concerning unwanted transitions, imperfect initial state, pulse shaping, control errors, and the effect of energy relaxations. The present work may provide help for laboratory researchers in a robust separation of chiral molecules.
A novel optical method for distinguishing chiral molecules is proposed and validated within a quantum simulator employing a trapped-ion qudit. This approach correlates the sign disparity of the dipole moment of chiral molecules with distinct cyclic evolution trajectories, yielding the unity population contrast induced by the different non-Abelian holonomies corresponding to the chirality. Harnessing the principles of holonomic quantum computation (HQC), our method achieves highly efficient, non-adiabatic, and robust detection and separation of chiral molecules. Demonstrated in a trapped ion quantum simulator, this scheme achieves nearly 100% contrast between the two enantiomers in the population of a specific state, showcasing its resilience to the noise inherent in the driving field.
Molecular chirality plays a crucial role in physics, chemistry, life sciences and pharmacology. Nowadays, the chiral discrimination and control at the single-molecule level is urgently needed to reveal the origin of the chirality-relevant phenomena by recovering the information disturbed by the ensemble averaging. The method of magnetic resonance (MR), as one of powerful tools for structure analysis, is blind to the molecular chirality in the absence of a chiral reagent. Here we propose and experimentally demonstrate a direct MR-based method for determining the chirality at the single-molecule level through constructing the symmetry-breaking dynamics of nearby nuclear spins. In principle, the mirror asymmetry of two enantiomers in real space is manifested by breaking the joint symmetry of the mirror reflection and time reversal in spin space under spin dynamics. Experimentally, two enantiomers are indistinguishable from the dynamics of strongly-coupled but unpolarized nuclear spins, but diverge evidently in the dynamical results that break the field-inversion symmetry after spins are polarized. Our method and results will benefit the study of chirality-induced properties in the fields of chemistry and biology.
Chiral discrimination that is efficient at detecting tiny amounts of chiral substances, especially at the single-molecule level, is in great demand. Here, we propose a single-shot nondestructive quantum sensing method addressing such an issue. Our scheme consists of two steps. In the first step, the two enantiomers are prepared in different rotational states via microwave enantio-specific state transfer. Then, chiral discrimination is transferred to quantum hypothesis testing. In the second step, we for the first time introduce a nondestructive quantum-state detection technique assisted with a microwave resonator for chiral discrimination, through which the molecular chirality is determined by the sign of the output signals. Using a typical chiral molecule, 1,2-propanediol, and an experimentally feasible model based on spherical Fabry–Pérot cavity, we show that the molecular chirality of slowly moving enantiopure gaseous samples with 10 2 –10 3 molecules can be highly credibly distinguished in a single-shot detection. By further trapping chiral molecules, it is promising to achieve chiral discrimination at the single-molecule level by using our approach.
Chiral discrimination of enantiomeric biomolecules is vital in chemistry, biology, and medicine. Conventional methods, relying on circularly polarized light, face weak chiroptical signals and potential photodamage. Despite extensive efforts to improve sensitivity under low-photon exposure, classical chiral probes remain fundamentally bounded by the shot-noise limit due to quantum fluctuations. To beat these limitations, we demonstrate quantum-elevated chiral discrimination using continuous-variable polarization-entangled states as moderate-photon-flux, high-sensitivity, quantum-noise-squeezed chiral probes. We achieve a 5 dB improvement beyond the SNL in distinguishing L- and D-amino acids in liquid phase. This non-destructive, biocompatible protocol enables high-sensitivity chiral analysis, with broad implications for drug development, biochemical research, environmental monitoring, and asymmetric synthesis.