An integrated device with high performance multi-function generators and time-to-digital convertors
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2017-01-01 |
| Journal | Review of Scientific Instruments |
| Authors | Xi Qin, Zhifu Shi, Yijin Xie, L. Wang, Xing Rong |
| Institutions | University of Science and Technology of China |
| Citations | 21 |
| Analysis | Full AI Review Included |
Integrated Quantum Control Systems: A 6CCVD Technical Analysis
Section titled âIntegrated Quantum Control Systems: A 6CCVD Technical AnalysisâExecutive Summary
Section titled âExecutive SummaryâThis research describes a high-performance, integrated, re-configurable device crucial for advancing Nitrogen-Vacancy (N-V) center based quantum applications, including quantum computation and metrology.
- Close-Loop Control: The device implements a fully integrated âclose-loopâ control system combining Arbitrary Waveform Generation (AWG), high-resolution Pulse Generation, and Time-to-Digital Conversion (TDC) on a single FPGA platform.
- Ultra-High Resolution Pulsing: The pulse generator achieves a superior non-dead-time output with a 50 ps time resolution (Least-Significant-Bit, LSB) and exceptional stability, maintaining a jitter below 25 ps across a wide 1 ns to 500 ms range.
- High-Speed Waveform Synthesis: Dual AWG channels operate at a 1 Gsps sampling rate with 16-bit amplitude resolution and a 500 MHz analog bandwidth, vital for complex microwave control pulses required by N-V centers.
- Precision Photon Timing: The FPGA-based TDC achieves a high measurement precision of 23 ps (LSB) with a dynamic range extending up to 42 seconds, essential for detecting photon arrival times from N-V centers.
- Low Noise Floor: The analog output shows strong digital noise suppression, measured better than -143 dBm/Hz at 1 GHz, ensuring clean RF signal delivery critical for maintaining N-V spin coherence.
- Material Relevance: This work directly supports research into quantum solid-state systems, explicitly requiring high-quality host materials such as Single Crystal Diamond (SCD) for N-V centers.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Core Application | N-V Centers in Diamond | N/A | Quantum computation & metrology |
| Device Architecture | Integrated Close-Loop System | N/A | AWG, Pulse Gen, TDC on Xilinx Virtex-7 FPGA |
| AWG Channels | 2 | Channels | Output via 16-bit DAC Board |
| AWG Sampling Rate | 1 | Gsps | Double-Data-Rate mode |
| AWG Resolution | 16 | bit | Amplitude resolution |
| AWG Bandwidth (Max) | 500 | MHz | Output Low-Pass Filter (LPF) cut-off |
| AWG Noise Suppression | < -143 | dBm/Hz | Digital noise suppression at 1 GHz |
| Pulse Channels | 12 | Channels | 3.3 V TTL output drivers |
| Pulse Time Resolution | 50 | ps | Duration and delay (LSB) |
| Pulse Jitter (STD) | < 25 | ps | Stability range: 1 ns < t < 500 ms |
| TDC Precision (LSB) | 23 | ps | Time measurement precision |
| TDC Dynamic Range | 42 | seconds | Maximum time interval measurement |
| TDC DNL/INL Error | -0.95/+0.9 / -0.7/+4.2 | LSB | Before Look-Up-Table (LUT) correction |
| I/O Termination | 50 | Ω | Sub-Miniature version A (SMA) |
| Overall System Latency | ~100s | ns | Excitation pulse to response signal |
Key Methodologies
Section titled âKey MethodologiesâThe integrated close-loop control device is achieved through the modular implementation of high-speed digital and analog circuits managed by a single FPGA.
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Hardware Platform:
- The digital compartment, power management, and pulse drivers are implemented on a 12-layer integrated Printed Circuit Board (PCB).
- Digital control uses a Xilinx Virtex-7 FPGA (XC7VX485T-ffg1761), providing central management for waveform generation and time-to-digital conversion.
- The analog compartment is a separate 10-layer DAC board connected via high-speed AMP-1469169-1 connectors.
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Arbitrary Waveform Generation (AWG):
- Waveform data (16-bit resolution) is pre-stored in external 1 GB DDR3 memory.
- Data is clocked out at 1 Gsps using the Double-Data-Rate (DDR) mode driven by 500 MHz clocks, via OSERDES modules in the FPGA.
- Digital-to-Analog conversion utilizes dual AD9139 ASIC chips.
- Output signals are amplified to 2 V peak-to-peak and filtered by an 11-order low-pass Butterworth filter (500 MHz cut-off).
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High-Resolution Pulse Generation:
- Achieved via a time interpolating method within the FPGA (non-dead-time pulse generator).
- A Coarse Pulse Module provides 1.25 ns time resolution (800 MHz clock period).
- A Fine Pulse Module uses a delay chain to provide real-time adjustment, achieving 50 ps resolution.
- Output is driven by 3.3V TTL drivers (SN74AVC1T45 transceiver and BUF602 high-speed buffer) optimized for 50 Ω termination.
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Time-to-Digital Convertor (TDC):
- Implemented via a cascaded carry chain structure within the Virtex-7 FPGA, operating with a 125 MHz system clock.
- A high-speed comparator (LMH7322) translates the input photon signal (from an Avalanche-Photon-Diode) to the Low-Voltage-Differential-Signaling (LVDS) electrical level.
- Fine time resolution (23 ps) is achieved by recording the signalâs leading edge position within the delay elements of the carry chain (producing a thermometer code).
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe successful replication and scaling of this high-performance quantum control system are fundamentally dependent on the quality and specificity of the diamond material used to host the N-V centers. 6CCVD is positioned as the ideal partner to supply the enabling MPCVD diamond platform.
| Project Requirement | 6CCVD Material & Service Recommendation | Value Proposition for Engineers & Scientists |
|---|---|---|
| High-Purity N-V Hosting | Single Crystal Diamond (SCD): Ultra-high purity, low-strain MPCVD diamond wafers are mandatory for maximizing N-V spin coherence time (T2*) and achieving the stable quantum states referenced in the paper. We control nitrogen incorporation (P1 defects) for optimal N-V creation. | Guaranteed CVD growth control tailored for quantum applications, ensuring defect density and purity meet stringent quantum metrology standards. |
| Microwave Integration Interface | Custom Polishing (Ra < 1 nm for SCD): Clean, atomically flat surfaces are required for precision integration of the high-speed RF/microwave circuitry (AWG output) and efficient optical collection of photons detected by the TDC. | Industry-leading surface finish minimizes microwave scattering loss and maximizes photon extraction efficiency, crucial for systems with < 100 ns latency. |
| Electrode/Antenna Integration | Custom Metalization Services: Integration of the 50 Ω SMA-terminated pulse channels often requires custom metallic antennas or striplines directly on the diamond surface. We offer thin-film deposition of Ti, Pt, Au, Pd, W, or Cu at custom layer thicknesses. | Seamless integration with high-frequency control electronics; ensures ohmic contact and robust interfaces capable of handling 3.3V TTL signal levels with sub-nanosecond rise times. |
| Scaling & Modularity | Large-Area Diamond Wafers (PCD/SCD up to 125mm): The modular nature of this hardware (upgradeable FPGAs, PCBs) suggests a pathway to scaling quantum experiments. We provide large-area PCD or SCD wafers to accommodate increasingly complex array designs. | Facilitates R&D scaling beyond table-top experiments towards commercial quantum devices, maintaining high-grade material quality across large dimensions. |
| Alternative Solid-State Defects | Boron-Doped Diamond (BDD): For replicating research on other solid-state systems mentioned (defect spins in silicon carbide, phosphorus in silicon), our BDD films offer excellent conductivity and robustness for electrochemical and sensor applications. | Versatile material platform supporting a broad spectrum of solid-state physics research beyond traditional N-V centers. |
| Material Consultation | In-House PhD Engineering Support: Our team provides direct technical consultation on matching diamond crystallographic orientation, defect concentration, and surface termination to the specific requirements of integrated AWG/TDC control schemes. | Accelerate design cycles and optimize material selection for demanding close-loop quantum feedback systems. |
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
A highly integrated, high performance, and re-configurable device, which is designed for the Nitrogen-Vacancy (N-V) center based quantum applications, is reported. The digital compartment of the device is fully implemented in a Field-Programmable-Gate-Array (FPGA). The digital compartment is designed to manage the multi-function digital waveform generation and the time-to-digital convertors. The device provides two arbitrary-waveform-generator channels which operate at a 1 Gsps sampling rate with a maximum bandwidth of 500 MHz. There are twelve pulse channels integrated in the device with a 50 ps time resolution in both duration and delay. The pulse channels operate with the 3.3 V transistor-transistor logic. The FPGA-based time-to-digital convertor provides a 23-ps time measurement precision. A data accumulation module, which can record the input count rate and the distributions of the time measurement, is also available. A digital-to-analog convertor board is implemented as the analog compartment, which converts the digital waveforms to analog signals with 500 MHz lowpass filters. All the input and output channels of the device are equipped with 50 Ω SubMiniature version A termination. The hardware design is modularized thus it can be easily upgraded with compatible components. The device is suitable to be applied in the quantum technologies based on the N-V centers, as well as in other quantum solid state systems, such as quantum dots, phosphorus doped in silicon, and defect spins in silicon carbide.