stm:logbook
Logbooks
Download here (measurementslog.pdf) template for printed logbook. It is very important to keep a rigorous logbook for every measurement (measurementslog.pdf)and for any maintenance action (maintenancelog.pdf), either on the STM or on the cryostat. A notebook is provided, to make notes. Nevertheless NEVER FORGET to fill in the above provided template AND the below more schematic logbook.
Log here the cooldowns: Name_setup/Date-start/He-level start/He-level end/Sample/T-range/Magnetic field range/Date-end/Notes. Under “Notes” report whether He has been refilled during the cooldown. End date is defined when the sample/insert is taken out to air.
| Name STM/setup | Name | Date start (dd/mm/yy) | He-start (mm) | He-end (mm) | Sample | T-range (K) | H-range (T) | Date-end (dd/mm/yy) | Notes |
|---|---|---|---|---|---|---|---|---|---|
| F-STM/green-c. | federica | 10-03-06 | 460 | 200 | HOPG | 300-5 (VTI) | none | 15-03-06 | He refilled, Z-motor OK. |
| F-STM/green-c. | federica | 17-03-06 | 465 | 480 | MoGe(55nm)/Au(2+2nm) | 300-4 (VTI) | none | 22-03-06 | He-refill, 20-03-06, 0-540mm, 22-03-06, 380-480mm, Z-motor OK first cooldown, 2nd cooldown fails @ 20K. |
| F-STM/green-c. | federica | 23-03-06 | 440 | 390 | MoGe(55nm)/Au(2+2nm) | 300-4 (VTI) | none | 25-03-6 | He-refill, 24-03-06, 0-540mm, Z-motor OK. |
| F-STM/green-c. | federica | 25-03-06 | 390 | 540 | LSMO(62nm) on NGO | 300-180 (VTI) | none | 27-03-06 | He-refill, 27-03-06, 165-540mm, Z-motor stops SUDDENLY at ~180K. NOTE: I set the spring preload higher (Fs,l~45-50gr) before cooling. |
| F-STM/green-c. | federica | 27-03-06 | 540 | 400 | LSMO(62nm) on NGO | 290 (VTI) | none | 29-03-06 | Problems: found out that electrical contact sample-to-sample holder was broken. Silver paste cracked off, it explains fully Z-motor “problem” above. |
| F-STM/green-c. | federica | 29-03-06 | 395 | 200 | LSMO(62nm) on NGO | 290-4 (VTI) | 0 to +7.88 | 04-04-06 | He-refill:31-03-06, 0-540mm - He-refill:03-04-06, 0-530mm, 03-04-06:magnet quench at 7.88 Tesla. ~20 lts. of Helium are lost. He-refill:03-04-06: 202-410mm. Z-motor OK, at base T and also after quench. |
| green-c | federica | 05-04-06 | – | – | – | – | – | – | Helium refill:0-515mm |
| F-STM/green-c. | federica | 05-04-06 | 490 | 270 | LSMO(20nm) on STO | 300-17 (STM) | +0 to +7 | 12-04-06 | He-refill:07-04-06, 0-515mm. He-refill:09-04-06, 0-515mm. He-refill:12-04-06, 20-530mm. Z-motor OK till lowest T |
| F-STM/green-c. | federica | 12-04-06 | 200 | 170 | PCMO(80nm) on STO-Nb | 300-50 (STM) | 0 to +7 | 14-04-06 | He-refill:13-04-06, 0-520mm. Z-motor OK. |
| F-STM/green-c. | federica | 14-04-06 | 170 | 0 | BSSCO, crystal | 300-50 (STM) | none | 14-04-06 | let cryostat warm up for Easter. Z-motor OK. |
| green-c | federica | 15-04-06 | – | – | – | – | – | – | start warming up |
| green-c | federica | 20-04-06 | – | – | – | – | – | – | RT (28 Ω) reached, start pumps |
| green-c | federica | 24-04-06 | 0 | 540 | precooling and cooling | – | – | 25-04-6 | Problem with λ-plate pumping tube (leak). See blog for explanation. Preoceed with cooling down anyway. |
| F-STM/green-c | federica | 26-04-06 | 530 | 410 | PCMO(80nm) on STO-Nb | 300-50 (STM) | 0 to +7.3 | 28-04-06 | Z-motor OK. Sample does not show CO-melting. Thinner spot? Magnet OK. |
| F-STM/green-c | federica | 28-04-06 | 535 | 400 | PCMO(80nm) on STO-Nb | 300- 10(STM) | 0 to +7.3 | 17-05-06 | Z-motor always OK. Several He-refills… |
| F-STM/green-c | federica/simon | 17-05-06 | 540 | several refills | NbSe2 (Leiden Xtal) | 300-5 (STM) | none | 23-05-06 | Z-motor OK down to base T. |
| F-STM/green-c | federica/simon | 23-05-06 | 530 | several refills | BSCCO (Ming Li) | 300-4 (STM) | none | 09-06-06 | Z-motor works OK -sometimes slow- down to 4K on STM for at least 4 different consecutive cooldowns. On 09-06-06 it becomes problematic at low T. Take out sample. Z-motor looks ok, contamination appears to be the problem. |
| F-STM/green-c | federica | 09-06-06 | 170 | several refills | BSCOO (Ming Li) | 300-4 (STM) | none | 15-06-06 | 2 times at base T and both times Z-motor works. Sample contaminated after 2 cooldowns. Take it out to cleave it. |
| F-STM/green-c | federica | 15-06-06 | 540 | several refills | BSCCO (Ming Li) | 300-4(STM) | none | 20-06-06 | Z-motor blocks at 4K due to contamination (while cooling down too fast again T-stm undershooted). At 4K, in liquid, changed the Z-motor driving period from 100μs to 150μs. This change un-blocked the motor, which then worked again and VERY FAST at 4K! Sample looks nevertheless contaminated (wide gaps, no coherence peaks). This and the critical slip-stick of the motor points to contamination problems, maybe now more than normal because of N2 leaking into the He-lines and tank from N2 tank -see issue of λ-plate pumping line being damaged after quench- |
| F-STM/green-c. | federica | 20-06-06 | 540 | several refills | NbSe2 #8 no I2 (R.H.) | 300-4 (STM) | none | 27-06-06 | Bias divider by 100. Used metal film resistors. 2 times at base T and both times Z-motor OK. (not even slow). Note: I did not refill LN2 tank this time. |
| green-c. | federica | 30-06-06 | 200 | n.a. | empty | n.a. | n.a | 30-06-06 | Found that the bolds of the top flange of the VTI were pretty loose. Due to the fact that the o-ring is made of In, this might cause leaks in the vacuum interspace. This might explain the high boil-off. Pumped for few hrs with rotary and diffusion pump. If there's ice condensed inside the interspace, this won't help much. Only warming up the cryostat will help. |
| F-STM/green-c. | federica/simon | 30-06-06 | 490 | several refills | LSMO/STO-2.0deg STO. (L309) | 300-50 | none | 17-07-06 | Z-motor OK. |
| F-STM/green-c. | simon | 17-07-06 | 540 | several refills | LCMO/STO-2.0deg STO (L402) | 300-100 | none | 27-07-06 | Z-motor OK. |
| F-STM/green-c. | simon | 17-07-06 | 540 | several refills | LSMO/STO-Nb 5nm (L317) | 300-100 | none | 10-08-06 | Z-motor Ok. Sample was taken out once for sample cleaning and tip re-cutting. |
| F-STM/green-c. | federica/simon | 10-08-06 | 544 | 425 | LSMO/STO (20nm) (old L307) | 300 | none | 15-08-06 | “Streak” problem. Sample looks bad. |
| F-STM/green-c. | federica/simon | 16-08-06 | 544 | several refills | Old thick flat Au on MoGe (may06) | 300 | none | 21-08-06 | Test (“intermezzo”) |
| F-STM/green-c. | federica/simon | 22-08-06 | 544 | several refills | LCMO/STO-Nb 100nm (L407) | 300-25 | 0-7 | 11-09-06 | Z-motor OK. Magnet power supply breaks on friday 25-08-06. The next monday swap broken power supply with older Cryogenic SMS80C from AMC group. After about 1 week imaging becomes more and more difficult (see notes). Contamination? Oxigen depletion of the 1st layers? |
| F-STM/green-c. | federica | 11-09-06 | 544 | 350 | Old thick flat Au on MoGe (may06) | 300-200 | none | 12-09-06 | Test (“intermezzo”) |
| F-STM/green-c. | federica | 12-09-06 | 544 | several refills | LCMO/Nb:STO (50nm) L414 | 300-38 | none | 18-09-06 | a-axis growth clear in topo. On 13-09-06, took out the sample and re-cut the tip. Re-cooled right after. Sample and tip OK, still a-axis growth. Re-cooled to 38K. |
| F-STM/green-c. | federica | 18-09-06 | 510 | 300 | Old Au on MoGe (may06) | 300-100 | none | 19-09-06 | Z-motor OK. Sample/tip looked contaminated at 100K. |
| F-STM/green-c. | federica | 19-09-06 | 544 | 415 | Old Au on MoGe (may06), same as above | 300 | none | 20-09-06 | Initially very good conditions. After pulsing the tip, very noisy. See logbook. |
| F-STM/green-c. | federica | 20-09-06 | 415 | several refills | Old Au on MoGe (may06), same as above | 300-35 | none | 25-09-06 | Z-motor OK. |
| F-STM/green-c. | federica/simon | 25-09-06 | 370 | several refills | LCMO(50nm)/Nb-STO L414, 3rd piece | 300-50 | none | 28-09-2006 | 26-09-06, take out again to “restore” the tip. Had to do this several times afterwards. On 28-09-06 “refreshing” the tip does not help anymore. Take out to etch a W tip. Z-motor OK. |
| F-STM/green-c. | federica/simon | 28-09-06 | 400 | several refills | LCMO(50nm)/Nb-STO L414, 3rd piece | 300-44 | none | 05-10-06 | W-tip (etched). Initially topo+STS ok. Z-motor OK. |
| F-STM/green-c. | federica | 06-10-06 | 350 | several refills | LCMO(50nm)/Nb-STO L414, 4th piece | 300 | none | 06-10-06 | PtIr tip, cut |
| F-STM/green-c. | federica/simon | 09-10-06 | 544 | several refills | LCMO(50nm)/Nb-STO L421 | 300-50 | none | 10-06-06 | W-tip (etched). RT noisy topography. |
| F-STM/green-c. | federica/simon | 19-10-06 | 500 | several refills | LCMO(50nm)/NGO L422 | 300-149 | 0 to +7 | 04-11-06 | Sample straight from sputtering system to STM, only ~3 hrs gap in air, Z-motor OK. |
| green-c. | federica | 06-11-06 | – | – | warm up | – | – | Cryostat warms up in the w.e. because of a leak in the VTI-He tank separation vacuum space | |
| green-c | federica | 06-11-06 | 0 | 470 | Pump superinsulaion & interspace | – | – | 13-11-06 | Diffusion pump: oil had to be changed. Changed (50ml, silicon oil 705) on 10-11-06. Recool on 13-11-06, from RT with Helium directly. Capillaries not flushed - needle valve remained closed and VTI+tank kept on clean He pressure during warm up. 100 lt of helium were used to cool. Needle valve opens, there is flow. Everything OK. |
| F-STM/green-c. | federica | 13-11-06 | 470 | several refills | LCMO(50nm)/NGO L422 | 300-200 | none | 29-11-06 | Z-motor OK. Tip had to be re-cut few times. |
| F-STM/green-c. | federica | 29-11-06 | full | several refills | LCMO(50nm)/NGO L429 | 300-200 | none | 23-01-2007 | Z-motor OK. Cryostat warmed up during Xmas with sample inside |
| F-STM/green-c. | federica | 22-01-07 | full | several refills | LCMO(50nm)/NGO L429 with Nb-tip (PCAR) | 300-30 | none | 29-01-07 | TEST: Point-Contact Andreev Reflection. Z-motor stops at 30K. When STM out, found Z-motor to be loose (Fs,l=20gr instead of 50gr). This -and some contamination- might explain the problems. |
stm/logbook.txt · Last modified: 2007/01/29 18:05 by galli