Molecular and Materials Science

Transcription

1 Canada s national laboratory for particle and nuclear physics Laboratoire national canadien pour la recherche en physique nucléaire et en physique des particules Molecular and Materials Science µsr and β-nmr: past present and future Reiner Kruecken Science Division Head TRIUMF Rob Kiefl Professor of Physics University of British Columbia Accelerating Science for Canada Un accélérateur de la démarche scientifique canadienne Owned and operated as a joint venture by a consortium of Canadian universities via a contribution through the National Research Council Canada Propriété d un consortium d universités canadiennes, géré en co-entreprise à partir d une contribution administrée par le Conseil national de recherches Canada

2 Outline Context of Molecular & Materials Science at TRIUMF Centre for Molecular & Materials Science International context Outputs Prof. Rob Kiefl, UBC Accomplishments Future plans Funding scenarios Summary Nov. 13, 2013 IPR - MMS 2

3 Context Q 1: What is the role of TRIUMF in supporting Canadian and international scientists and students (in Molecular and Materials Science)? Nov. 13, 2013 IPR - MMS 3

4 TRIUMF s Research Program Nov. 13, 2013 IPR - MMS 4

5 Demographics and funding context Centre for Molecular and Materials Science (CMMS) User facility (since 1988) supported by NSERC (currently Major Research Support grant) Scientists TRIUMF (NRC) 2 Joint faculty 1 Technicians NSERC-MRS 3 3 Facility operation and user experiments are fully supported by CMMS staff Funding: NSERC-MRS: $0.44M per year TRIUMF: $0.10M per year User-fees: $0.10M per year + Liquid Helium Cost (until 2013) $0.42M per year (75% TRIUMF, 25% users) Nov. 13, 2013 IPR - MMS 5

6 Centre for Molecular and Materials Science µsr facility Muonium chemistry Muoniated free radicals Muon as probe of bulk magnetism and superconductivity Complementary to neutron scattering (sensitive to different time scale of magnetic fluctuations) often same material studied using neutrons + muons M15 M9B M9A M20 (CFI) β-nmr facility Magnetic and electronic properties of thin films and interfaces with nm depth control Complementary to low energy muons at PSI but probing much longer timescales (sec vs. microsec) Nov. 13, 2013 IPR - MMS 6

7 Recent investments into CMMS facility New Muon beamlines M9A (TRIUMF) and M20 (CFI) Major investments (>$9M) to expand MuSR program New CMMS liquefier to recover LHe from CMMS experiments ($1.4M) M9A M20 12/9/2011 TRIUMF ACOT December

8 BL1A / Meson Hall Issues M9 beamline moving due to swelling shielding block M9B M9A M20 Motion went beyond capability of seal flexibility Blank-off installed fall 2012 mid-term solution being investigated engineering study in for full repair solution Beamline 1A (BL1A) Target T2 Nov. 13, 2013 IPR - MMS 8

9 TRIUMF s role in the Canadian and international community µsr Only µsr facility in North America Comparable capabilities to PSI but some unique experimental features, flexible set-ups complementary to ISIS (UK) & JPARC(Japan) - pulsed vs. continuous wave (CW) β-nmr Unique worldwide (ISOLDE has capability but no advanced spectrometer or depth control) Complementary to low-energy µsr; studies different time scales è Both methods provide unique information, which complement other techniques (e.g. neutrons, NMR) Nov. 13, 2013 IPR - MMS 9

10 TRIUMF s role in the Canadian and international community User community ( ): 490 M20 renewal Nov. 13, 2013 IPR - MMS 10

11 Molecular & Materials Science Output Creating Leaders: Trainees undergrad MSc (grad)* PhD (grad)* PDF MMS (* data from TRIUMF or supervised at TRIUMF) Advancing Knowledge: Publications Effect of reduced beam time in 2011 Nov. 13, 2013 IPR - MMS 11

12 Highlights Q 2: To what extent are TRIUMF s research activities, on a national and international scale, considered leading edge? Q 3: To what extent has key knowledge been generated as a result of TRIUMF s activities? Q 4: To what extent has TRIUMF elevated Canada s reputation and international leadership in physics? Nov. 13, 2013 IPR - MMS 12

13 Materials Science Isotopes for Science and Medicine Harnessing particles and beams for discovery and innovation Magnetism and superconductivity in bulk materials Magnetic and electronic properties at interfaces, on surfaces, and in thin films Muonium Chemistry, Muoniated Free Radicals Nov. 13, 2013 IPR - MMS 13

14 Broad Scientific Goals explore and control the electronic/magnetic properties of new materials both in the bulk and near interfaces and surfaces. impact is on future devices that will exploit these properties e.g. better magnetic read heads in computers, superconducting RF cavities that operate a much higher E- fields, and new advanced Li batteries. µsr and β NMR have unique capabilities in this area that complement other techniques such as neutron scattering, light scattering, and NMR. Nov. 13, 2013 IPR - MMS 14

15 Properties of the muon and 8 Li µ + e + + ν e + ν µ 8 Li 8 Be + e - + ν e θ Spin = 1/2 γ = MHz/T <A>= 0.33 Polarization = 95% Lifetime = (7) µs Spin=2, Q=33 mb γ =6.30 MHz/T <A>=-0.30 Polarization= 70% Lifetime= 1.2s Nov. 13, 2013 IPR - MMS 15

16 Muon Chemistry at TRIUMF Muons are the best test of first principles calculations on chemical reactions e.g. Mu+H 2 à MuH +H Mu=µ + e - He ++ µ e - D. Fleming et al, Science 331, 448 (2011); J. Chem. Phys. 135, (2011). Don Fleming (UBC) 2012 APS Fellow * For MuSR work at TRIUMF Nov. 13, 2013 IPR - MMS 16

17 The muon as a unique and powerful probe of superconductivity and magnetism TRIUMF is poised to make important contributions in this area because: 1. the muon is the most sensitive probe of internal magnetic fields. 2. It can be applied to any material and under extreme conditions. Talk Luke The collective many body effects in solids are rich and for the most part unpredictable and thus open for experimental discovery, e.g. High Temperature Superconductivity Uemura et al., PRL 1989 (719 citations) TRSB in Sr 2 RuO 4, Luke et al., Nature 1998 (446 citations) Cooperative paramagnetism in Tb 2 TiO 7, Gardner et al., PRL (270 citations) Talk Dunsiger Brewer (2009), Gingras (2010 TRIUMF PDF), Gaulin (2011), Bonn (2012) and Forrest (2013) (β-nmr) all CAP Brockhouse medal winners. Nov. 13, 2013 IPR - MMS 17

18 P. Carlo et al. Nature Materials 11, (2012): New magnetic phase diagram of (Sr;Ca) 2 RuO 4 Talk Luke Old? New Nov. 13, 2013 IPR - MMS 18

19 β-nmr at ISAC has great potential for discovering new collective phenomena in thin films and interfaces. A B Superconductor/vacuum, depth dependence of the order parameter. Superconductor/metal, proximity effect. Ferromagnet/metal, Ag/Fe magnetic multilayers GMR Talk MacFarlane Semiconductor/ferromagnetic, spintronics Insulator/vacuum, insulator/metal SrTiO 3 NMR Neutrons µsr LEµSR Β NMR Resonant x-ray diff. ARPES STM Insulator/insulator SrTiO 3 /LaAlO 3 topological insulators Polymers films Talk MacKenzie Forrest: 2013 Brockhouse medal winner Nov. 13, 2013 Forrest(2013) IPR - MMS 19

20 Critical slowing down of fluctuations in the induced SC order parameter in Ag/Nb films Morenzoni, Saadaoui et al., PRB 85, (R) (2012). Morenzoni is muon group leader at PSI, Saadaoui former PhD UBC β-nmr Li stopping distribution profile Nov. 13, 2013 IPR - MMS 20

21 Z. Salman et al., PRL 109, (2013). Salman former β-nmr PDF now PSI scientist Nov. 13, 2013 IPR - MMS 21

22 Materials Science Q 9: Are the proposed activities included in TRIUMF s 5-year plan appropriate and consistent with the needs and ambitions of the physics community, both in Canada and internationally? Will the plan elevate Canada s reputation and international leadership in nuclear medicine, nuclear physics, materials science, particle physics and accelerators research? Q 10: Do the requested resources and the laboratory s capabilities give reasonable confidence that the activities of the 5-year plan can be carried out to achieve the stated outcomes? Nov. 13, 2013 IPR - MMS 22

23 5 Y plan ARIEL Completion phase 1 comes on line in 2017 β-nmr receives 20 weeks of beamtime (factor of 4 increase). Impact in field of thin films interfaces will be significant and comparable to Low Energy Muons at PSI. Large increase in user base. It will be the same user base as for low energy muons at PSI. Requires additional manpower. 2. T2 target problem is fixed and M9 beamline is fully operational critical for extending the limits of µsr under extreme environments. installation of 2 nd dilution refrigerator (DR) for high pressure on M9B 2 nd DR can also be used to make a 1 mk demagnetization stage for ultra lowt, 20 times lower than is currently possible. Both capabilities are unique in the world and would re-establish TRIUMF as the world leader in this area. Beamlines are already the best. Nov. 13, 2013 IPR - MMS 23

24 5 Y plan (cont d) 3. All significant barriers to new users will be removed. New Liquefier eliminates all LHe charges TRIUMF supports program with additional $100k/yr operational funding, eliminating need for user fees User base will expand mainly from Canada, US and Japan. Requires additional manpower. Nov. 13, 2013 IPR - MMS 24

25 MMS Overview Scenarios core funding Sponsored activites Operational Budget NRC (liquefier operation, M&S, upgrades) A B C $1.8M* $1.0M $0.45M $0.3M Engineering Study for BL1A $2.0M $2.0M - NSERC MRS funding $2.2M $2.2M $2.2M $2.2M User fees (charge per hour beam time) $0.5M - $0.5M $0.5M * incl. LHe Nov. 13, 2013 IPR - MMS 25

26 Scenario B β-nmr is fully exploited with ARIEL II phase 1, elevating it to real user facility (Goals 1,2, Goal 5 partial) µsr program holds status quo with bare bones operations (Goal 5 ) User fees will continue, hampering growth of community (Goal 5 ) Budget impact on accelerator operations effects science è Reduced output resulting from reduced reliability Nov. 13, 2013 IPR - MMS 26

27 Scenario C reduced resources, restricted program Concentrate TRIUMF s research on particle and nuclear physics Reduce support for staff and operating activities with targeted, deep cuts Increased chances of major failure(s) leading to extended downtime è reduced science and HQP output, loss of users substantial downtime will drive users to seek alternative facilities and methods è loss of competitiveness, international leadership, and reputation; diminished relevance substantially delayed operation of ARIEL II phase 1 for β-nmr no engineering study for BL1A è operate BL1A until it breaks, user community will move elsewhere in case of major failure, no repair in , µsr program becomes irrelevant è Canada would curtail forefront international user-facility for Molecular & Materials Science with all its unique capabilities (Goals 1,2,5) Nov. 13, 2013 IPR - MMS 27

28 Summary 5-Year Plan outlines the opportunities to build on demonstrated strength and invest into sustained excellence. Funding requested will enable realization of the vision for CMMS: With ARIEL β-nmr is elevated to full international user facility, fulfilling demand by user community (Goals 1,2,5 ) µsr facility operates at full capacity, exploiting unique capabilities (Goal 5 ) National and international user community is expanded (Goal 5 ) è 5-Year Plan further elevates Canada s reputation in Molecular and Materials Science with muons and rare isotopes Nov. 13, 2013 IPR - MMS 28

29 Canada s national laboratory for particle and nuclear physics Laboratoire national canadien pour la recherche en physique nucléaire et en physique des particules Thank you! TRIUMF: Alberta British Columbia Calgary Carleton Guelph Manitoba McGill McMaster Montréal Northern British Columbia Queen s Regina Saint Mary s Simon Fraser Toronto Victoria Winnipeg York Merci Owned and operated as a joint venture by a consortium of Canadian universities via a contribution through the National Research Council Canada Propriété d un consortium d universités canadiennes, géré en co-entreprise à partir d une contribution administrée par le Conseil national de recherches Canada

30 BL1A operation is essential for MuSR program (M15, M20, M9) Neutron irradiations (TNF), 500 MeV Rb/Sr isotope production UCN facility (new beamline BL1U takes kicked beam from BL1A) M11 detector test facility (ATLAS, Belle-II, T2K/Hyper-K) Current situation Q1Q2 frontend of M9 has been removed T2/M9 port has been blanked off Task Force has evaluated the situation: T2 steady, M9 moving due to crumbling/swelling block Midterm plan Evaluate two repair options Reposition existing Q1Q2 in place to allow for further movement Built new Q1Q2 and position such that further movement can be followed Regain operation of M9A & M9B as soon as possible Long term plan ( ) Engineering study during next 5-Year Plan until 2018 Develop full refurbishment plan incl. cost estimate Act on this plan during 5-Year Plan BL1A update Oct. 04, 2013 ACOT - Science Division 30

31 M20 Nov. 13, 2013 IPR - MMS 31

32 Muons on Request Nov. 13, 2013 IPR - MMS 32