Quadrupole Deflector

An electrostatic quadrupole beam deflector (or DC turning quadrupole/quadrupole bender) uses a DC quadrupole electric field to bend a charged particle beam 90 degrees. The bending can be switched on and off by setting the voltages (+V and -V on opposite rods for 90 degree bending and GND on all rods for no bending). A ground enclosure is placed around the rods to reduce bending outside of the 90 degree quadrant due to fringe fields.

The SIMION Example: bender_cut (turning_quad_xy.gem) included an example geometry in SIMION. This example was updated in SIMION 8.1.2.20 to include the outer enclosure electrode around the rods for proper operation (reduce field outside). This uses circular rods to approximate the quadrupole field (hyperbolic potential lines), much like in SIMION Example: quad, and the ratio between rod radius and half-distance between rods remains the same.

Fig. 52 SIMION simulation of particles through 90 degree DC quadrupole deflector (based on SIMION Example: bender_cut (turning_quad_xy.gem)

Fig. 53 3D view of turning_quad_xy.gem example, which includes entrance and exit lenses.

Links

• Implementing a 4-way-90 degree Quadrupole Beam-Deflector into the MLLTRAP System, E. Gartzke, V. S. Kolhinen, D. Habs, J. Szerypo, and P. G. Thirolf – shows SIMION simulation for quad deflector (Fig 3)
• MODEL QID-900 Quadrupole Ion Deflector by Beam Imaging Solutions, provides a SIMION model of their quad deflector they sell commercially.
• Quadrupole Beam Deflector 30 kV – DREEBIT Quadrupole Beam Deflector with SIMION simulation
• Colutron SIMION 3D Geometry Files – includes SIMION model of beam deflector sold commercially. Also: model 900 quadrupole ion deflector (APACE Science)
• Cross Beam Ionizer Design for Plasma Monitoring Extrel Application Note GA-511D, AVS Conference 1996. – has SIMION simulation of quad deflector.
• DaolioFacchin1999. Daolio, S.; Facchin, B.; Pagura, C.; Tolstogouzov, A.; Konenkov, N. “Quadrupole secondary ion mass spectrometer for simultaneous detection of positive and negative ions” Rapid Communications in Mass Spectrometry, volume 13, issue 9, year 1999, pages 782-785 link doi(broken): 10.1002/(SICI)1097-0231(19990515)13:9<782::AID-RCM564>3.0.CO;2-L – has SIMION simulation of quad deflector
• im Fachbereich Physik der Freien Universitat Berlin eingereichte Dissertation, vorgelegt von, Oliver Gause, 25.04.2012. link – includes SIMION simulations of quad deflector
• MominBhowmick2008. Momin, T; Bhowmick, A; Gadkari, S C. “Development of a nano electrospray time of flight setup” Journal of Physics: Conference Series, volume 114, year 2008, pages 012053 doi:10.1088/1742-6596/114/1/012053 – shows SIMION simulation of quad deflector
• KimSaykally2003. Kim, Hack-Sung; Saykally, Richard J. “An ion beam reflectron/single-photon infrared emission spectrometer for the study of gas-phase polycyclic aromatic hydrocarbon ions: Testing proposed carriers of the unidentified infrared emission bands.” Review of Scientific Instruments, volume 74, issue 4, year 2003, pages 2488. doi:10.1063/1.1544418. link – Shows SIMION simulations of quad deflector
• Technical Design Report for High-Precision Experiments with Traps and lasers on Exotic Isotopes at Fair. link – shows SIMION simulations of quad deflectors.
• ElgerSchmidt2017. Elger, B. Schmidt, T. Krähling, S. Neuberger, F. Schäfer, R. Electrostatic simulation of a complete cluster deposition apparatus. Review of Scientific Instruments. volume 88, issue 6, year 2017, pages 063303 – SIMION simulator with quad deflector and quad mass filter, lenses, MPI, Poisson. doi:10.1063/1.4984968 link
• Other deflectors
  • KreckelBruhns2010. Kreckel, H.; Bruhns, H.; Miller, K. A.; Wa’hlin, E.; Davis, A.; Ho’ckh; S., Savin; D. W. “A simple double-focusing electrostatic ion beam deflector.” Review of Scientific Instruments, volume 81, issue 6, year 2010, pages 063304 doi:10.1063/1.3433485 link – alternative (non-quadrupole) beam deflector with SIMION simulation. Simulations also described in US patent # 8,309,936.
  • C. P. Welsch; J. Ullrich, et al. Ring of Fire. link – various other deflectors
  • Design of a novel Electrostatic Ion Storage Ring at KACST. M.O.A. ElGhazaly, S.M.Alshammari, C.P.Welsch, H.H.Alharbi. link – SIMION simulations of other deflectors