Scalable Cryogenic Quantum Dot Biasing using Memristor-based DC Sources

Core Concepts

Memristor-based DC sources offer a promising approach for scalable in-situ biasing of quantum dot arrays at cryogenic temperatures.

Abstract

This paper investigates the feasibility of using memristor-based DC sources for biasing quantum dot arrays at cryogenic temperatures. The key highlights are:

The authors demonstrate the cryogenic operation of a commercial operational amplifier (AD8605) down to 1.2 K, which is a critical component for the memristor-based DC source prototype.

The memristor-based DC source prototype is characterized at both room temperature and 1.2 K. At room temperature, the prototype exhibits a tunable output voltage range of 0.4 V to 0.65 V with a 10 mV resolution. At 1.2 K, the prototype can sweep a 0.4 V to 0.65 V range, but with a lower voltage resolution due to the higher resistance of the memristors at cryogenic temperatures.

The stability of the programmed output voltages is evaluated, showing a drift of only 1 μV/s at 1.2 K, which is compatible with the coherence time of spin qubits.

To address the power consumption and voltage resolution limitations of the discrete prototype, the authors propose a fully integrated CMOS-memristor approach. Simulations suggest this integrated design can reduce the power consumption to 10 μW per DC source and enable the integration of up to 300,000 DC sources at the 4.2 K stage of a dilution fridge, paving the way for large-scale quantum computing applications.

Stats

The memristor-based DC source prototype exhibits a voltage drift of approximately 1 μV/s at 1.2 K.
The power consumption of the AD8605 operational amplifier is around 10 mW at 1.2 K.

Quotes

"Memristor-based DC sources offer a promising avenue for in situ biasing of quantum dot arrays."
"Simulations reveal a reduction in power consumption, down to 10 μW per DC source and in footprint. This allows for the integration of up to one million eNVM-based DC sources at the 4.2 K stage of a dilution fridge, paving the way for near term large-scale quantum computing applications."

Key Insights Distilled From

Towards scalable cryogenic quantum dot biasing using memristor-based DC sources

by Pier... at arxiv.org 04-17-2024

https://arxiv.org/pdf/2404.10694.pdf

Deeper Inquiries

How can the voltage resolution of the memristor-based DC source be further improved beyond the 10 mV demonstrated in this work

To improve the voltage resolution of the memristor-based DC source beyond the 10 mV demonstrated in this work, one approach is to increase the number of memristors in the feedback loop. By adding more memristors in parallel, the total feedback resistance can be finely tuned, allowing for a more precise control of the output voltage. Each additional memristor contributes to the overall resistance, enabling smaller incremental changes in the output voltage for a given input. This exponential improvement in resolution with the number of memristors has been previously demonstrated in research. By scaling up the number of memristors, the voltage resolution can be increased to achieve even finer control over the output voltage.

What are the potential challenges in the monolithic co-integration of CMOS and memristor devices, and how can they be addressed

The monolithic co-integration of CMOS and memristor devices presents several potential challenges that need to be addressed for successful implementation. Some of these challenges include:

Process Compatibility: Ensuring that the fabrication processes for CMOS and memristor devices are compatible is crucial. Different material requirements and processing steps may need to be harmonized to enable monolithic integration without compromising device performance.

Thermal Management: Memristors can generate heat during operation, and effective thermal management is essential to prevent overheating and ensure reliable performance. Designing the integrated circuit layout to optimize heat dissipation and thermal conductivity is critical.

Reliability and Endurance: Memristors have specific endurance and reliability characteristics that need to be considered in the design. Ensuring that the integrated devices can withstand the operational requirements over an extended period is essential for long-term functionality.

Signal Interference: The integration of CMOS and memristor devices on the same chip can lead to signal interference and crosstalk issues. Proper isolation techniques and signal routing strategies need to be implemented to minimize interference and maintain signal integrity.

To address these challenges, collaborative research efforts between semiconductor manufacturers, device designers, and material scientists are essential. By optimizing the fabrication processes, improving thermal management strategies, enhancing device reliability, and mitigating signal interference, the monolithic co-integration of CMOS and memristor devices can be achieved successfully.

What other emerging non-volatile memory technologies, besides memristors, could be leveraged for cryogenic quantum dot biasing, and how would their performance compare

Besides memristors, other emerging non-volatile memory technologies that could be leveraged for cryogenic quantum dot biasing include Ferroelectric Tunnel Junctions (FTJs) and Valence Change Memory (VCM).

Ferroelectric Tunnel Junctions (FTJs): FTJs exhibit high resistance states, making them suitable for precise analog programming at cryogenic temperatures. Their inherent non-volatility and low power consumption characteristics make them promising candidates for quantum dot biasing applications. FTJs can offer resistance values in the megaohm range, enabling fine-tuning of output voltages with high precision.

Valence Change Memory (VCM): VCM, similar to memristors, can exhibit analog programmability down to cryogenic temperatures. VCM devices have been shown to have resistance values suitable for quantum dot biasing applications. Their compatibility with CMOS processes and potential for low-power operation make them attractive for integrated quantum computing systems.

Comparatively, FTJs may offer even higher resistance values than VCM, allowing for lower power consumption and finer voltage resolution in quantum dot biasing applications. However, the specific performance characteristics, scalability, and integration challenges of each technology need to be carefully evaluated to determine the most suitable option for cryogenic quantum dot biasing.