The Development Of Power Supply System For Ion Trap

Ion trap technology is widely used in the study of atomic frequency standards, quantum computing, mass spectrometry and other microscopic particles fields.A wide range of ion trap,Paul trap can be widely used because of its advanced nature.And Paul trap on the basis to develop a linear Paul trap reduces the RF heating problem of ions trapped in a Paul trap, and by adjusting the axial restraint potential changes a prisoner of the axial position of the ions,has a more extensive application.Linear Paul trap to work is inseparable from the power supply system, this article is for the Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences linear Paul trap design a complete power system, namely the ion trap power system.The design of the ion trap power supply system includes a DC power supply and RF power, combined with an embedded platform, computer-controlled.This paper analyzes the impedance characteristics of linear Paul trap, job characteristics and key parameters of the power supply requirements, completed the design target for the supply, implementation,development of power systems, power systems testing.Mainly for the following work:(1)Power design index of the proposed.Power design index of the proposed.According to the linear trap trapped principle, ion motion equation, the potential well depth, the proposed design specifications RF power: two-way symmetric output, frequency 2MHz~4MHz, voltage Vpp is 0~800V, distortion less than 1%.DC Power Specifications: 12 independent outputs with 10 V, 500 V, 1000 V three ranges, within each range voltage ripple is less than 1‰, voltage error is less than 1%.Meanwhile the power system must be programmed, and has a display function.(2)Scheme design.Analysis of the load impedance characteristic of the ion trap, with power and simple design specifications and operating principles, design a power system consists of precision programmable power supply and programmable RF power component.Software and hardware systems constitute the two main wells developed linear power supply system.Software system from the PC user layer software and lower machine control software via PC computer communications and to complete the power of programmable.Precision programmable power supply hardware combined linear power supply based on the principle of the PI regulator circuit, the output voltage can be adjusted to achieve the ripple smaller requirements.Programmable radio frequency source design schemes is small of DDS output signal through the three-level power amplifier circuit for amplifying power, and through the broadband matching network and filter network, the final output spectrum clean symmetrical sine wave.(3)Development of power systems.Based on MFC framework of the technology designuser interface, and uses dsPIC30F4011 as control core, to build the power control platform,and designs the software system controlled by single chip microcomputer.Design a sophisticated programmable power supply circuit diagram, component selection, and finally produce power under the program.On the basic theory of the radio frequency amplifying circuit,build the DDS signal generating circuit, designed the three-level circuit structure,discussed at various levels of schematics, characteristics, function, power amplification and synthesis methods, the design and production of the two cascaded 1:4 transmission line transformer impedance transformation circuit, reached for the broadband matching network and boost converter, and small sine wave distortion has been obtained by 7 order Chebyshev filter.RF power produced considering the electromagnetic compatibility, radiation shielding,high-power element cooling, PCB layout and other issues.(4)Power system testing. on the platform to build a good supply of software and hardware systems with machine overall test detected by a human issue commands from the host PC, microprocessor control system operation operability and accuracy.Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences shows that the actual use, of the ion trap power supply system can work well on the linear Paul trap success imprisoned 40Ca+ ion, the ion signal obtained crystalline state, to the design specifications.