Sample Delivery Methods
The table below summarizes the current sample handling capabilities at the LCLS. We are currently in the process of developing new sample delivery techniques, and users are encouraged to contact the Sample Environment Department to discuss requirements unique to their experiment - we are flexible.
|Liquid Jets ||1 µm - 10 µm||✅||✅|
|20 µm - 500 µm||⛔️||✅ ♻️|
|< 1 µm||✅||✅ ♻️|
|1 µm - 10 µm||⛔️||✅ ♻️|
|10 µm - 250 µm||⛔️||✅ ♻️|
|Liquid Drops||40 µm - 60 µm||⛔️||✅|
|Double Flow Focusing||All available sizes||✅||✅|
|Electrospinning (MESH)||All available sizes||✅||✅|
|High Viscosity||All available sizes||✅||✅|
|Aerosols||All available sizes||✅||⛔️|
✅ Available ⛔️ Not Available ♻️ Recirculation is available at some endstations.
Descriptions of Sample Delivery Methods
High flow rate experiments operating in ambient air or in a helium enclosure can be operated in a closed-loop recirculating system when the sample permits. Cylindrical liquid jets from 20 micron diameter and larger and liquid sheets of any thickness from a few 10’s of nanometers to several hundred micrometers can be recirculated. The minimum volume of sample needed to fill the swept volume of our recirculating system is typically a few ml for smaller jets, Larger sheets operating at greater than 150 ml/minute require a peristaltic pumping system with a higher swept volume. Details can be found on the pump section of our Equipment page.
Single fluid “Rayleigh Jets” can be used for experiments in which larger diameter, >20 microns, and high flow rate are acceptable. These jets are often used for pump-probe spectroscopies at the XPP endstation in a recirculating system. They can also be operated in vacuum without recirculation however their reliability is much higher outside of vacuum. The nozzles are made of straight walled polished quartz tubing but other materials are available. These jets are fairly reliable and users are usually able to operate on their own after a short training session.
Gas Accelerated, GDVN, or flow focused jets can be made much smaller than single fluid nozzles. They are commonly operated in vacuum for serial crystallography experiments – the reduced jet diameter, 1 to 4 microns reduces the background scatter. Flow rates are around 10 microliter per minute.
- >10 micrometers. Straight walled nozzles are used to make sheets from 13 microns thick and larger. As with cylindrical jets, these have fairly high flow rate and are operated in ambient conditions.
- 1 to 10 micrometers – converging nozzles are useful for making
- < 1 micrometer – gas accelerated nozzles make ultra thin sheets that can be operated in vacuum or atmosphere.
Aerosols are made by nebulization of liquids. GDVN, Electrospray, or gas assisted electrospray have been used. An aerodynamic lens stack made by Uppsala is owned by SLAC and is available to users. Aerosols are used primarily for single particle imaging. Solutions must have high particle density and low amounts of salts, buffers, or any nonvolatile material that cannot be evaporated from the sample.
Other SLAC sample delivery methods - descriptions coming soon.
- Flow Focusing & Mixers
- Drop on Demand
- High Viscosity Injection LCP
- Electrospray MESH
- Gas Sources and Cells
Non-SLAC User-owned Equipment
There are some methods not owned by SLAC that have been used at SLAC and may be available through collaboration.
- Acoustic Levitation
- Rowed Runner