Boston University Steers Qubit Phase with Tailored Drives

Controlling how quantum systems interact with their environment remains a key challenge in building strong technologies. A team at Boston University has revealed a new method using periodic driving, repeatedly applying an energy pulse, to manipulate the geometric phase within open quantum systems. Manipulating periodic energy pulses affects quantum systems interacting with their surroundings. Repeated application of these ‘drives’ controls changes to fundamental properties called geometric phases within complex systems exposed to environmental noise. This technique differs from previous methods relying on static adjustments; it offers greater adaptability in managing external disturbances affecting open quantum systems. The researchers have detailed how precisely timed energy pulses manage subtle changes in a quantum system’s state, similar to tracing a path around an object where the final position depends not just on starting and ending points but *how* you got there. These ‘geometric phases’, key for potential technologies like quantum computing, are easily disrupted by environmental noise affecting open quantum systems, those interacting with their surroundings.

The team investigated manipulating these geometric phases within such vulnerable systems using periodic driving, repeatedly applying an energy pulse to influence interactions. To quantify this control, they introduced a method separating the effects of both external drives and inherent dissipation from the system; understanding whether drive parameters enhance or suppress environmentally-induced distortions is vital. Precisely tuning these pulses offers strong protection against decoherence, paving the way for more stable quantum devices.

Periodic Driving Enables Control Over Quantum System Environmental Sensitivity Gate fidelity increased approximately four-fold compared with previous static inversion symmetry breaking techniques demonstrated by Wang et al., surpassing limitations previously preventing precise control over bath effects at timescales below 50 femtoseconds. The improvement originates from dynamic manipulation using periodic driving, allowing redistribution of energy among quasienergy sidebands influencing coupling to an environmental thermal bath. Floquet spectral steering, the redistribution of dynamics via these bands, enables suppression or enhancement of deformation within the geometric phase depending on how quickly drive parameters interact with those of the surrounding environment. Periodic driving can either suppress or enhance environmental disturbances affecting a quantum system’s geometric phase; this control arises from redistributing energy amongst ‘quasienergy sidebands’, altering its interaction strength with surrounding thermal fluctuations. Analysis utilising Floquet theory revealed that changes in behaviour depend not only on drive strength but also upon matching driven system frequencies to those present within the bath environment itself. A novel numerical technique, process-tensor time-evolving matrix product operator, enabled accurate simulation of complex interactions over timescales exceeding typical environmental correlations and allowed researchers to introduce a measurement quantifying distortion of the quantum trajectory caused by dissipation beyond purely unitary conditions. This provided insight into cooperative effects between periodic driving and the thermal bath. Periodic driving manipulates environmental impacts on key quantum characteristics Controlling unwanted environmental interactions is vital for realising stable quantum technologies such as advanced sensors or computational devices; this research focuses on a specific spin-boson model interacting with an Ohmic environment, simplifying how thermal fluctuations affect the system. Despite utilising a simplified ‘spin-boson’ model, describing interaction between quantum systems and their surroundings, its findings remain significant for advancing practical quantum device development. Pulsing energy into quantum systems, termed periodic driving, influences their interaction with surrounding environments according to researchers; manipulating quasienergy sidebands redistributes dynamics to manage environmental coupling strengths, as revealed by pathway analysis. The research demonstrated that periodically driven quantum systems exhibit altered geometric phase behaviour due to interactions with their environment. Researchers used a process-tensor time-evolving matrix product operator method to simulate these complex interactions and quantify distortion caused by dissipation in a spin-boson model coupled to an Ohmic bath. The findings establish periodic driving as a technique for managing the impact of environments on open quantum systems. 👉 More information🗞 Floquet Dressing and Bath Spectral Effects on the Geometric Phase of a Driven Dissipative Qubit✍️ Chirag Arora🧠 ArXiv: https://arxiv.org/abs/2609.16609 More like thisQuantum Research NewsIonQ wins four best-paper awards at quantum computing conferenceQuantum Research NewsResearchers Find Near-Perfect Quantum Data Transmission Via WeightingQuantum Research NewsWake Forest opens lab for room-temperature quantum processorsQuantum Research NewsWaterloo’s Tsen leads quantum nanoscale materials research as new chairStay currentSee today’s quantum computing news on Quantum Zeitgeist for the latest breakthroughs in qubits, hardware, algorithms, and industry deals. Tags: Muhammad Rohail T. As a quantum scientist exploring the frontiers of physics and technology. My work focuses on uncovering how quantum mechanics, computing, and emerging technologies are transforming our understanding of reality. I share research-driven insights that make complex ideas in quantum science clear, engaging, and relevant to the modern world. Latest Posts by Muhammad Rohail T.