EMFL FUTURE MAGNET SURVEY

High Field Magnets for the next decade

What are the objectives of this survey ?

Our aim is to establish a roadmap for the development of new magnets based on the needs of our users.

How long is the survey and what if I am only interested in very specific magnet types ?

There are no mandatory parts. Participants may skip magnets and magnet categories at their convenience. Navigation buttons and intermediate tables of contents are provided to facilitate a rapid completion of relevant parts.

How is the survey organized ?

The survey lists potentially interesting magnets organized in 4 categories. Participants are invited to choose magnets that are essential for their research and rate the importance of specific parameter values by selecting one of the options; useful, important or extremely important.

What if the magnet I want doesn’t appear in the list ?

A text field at the end of the survey permits additional suggestions. Alternatively, participants may send their ideas to magnets.survey@lncmi.cnrs.fr

Is the survey anonymous ?

Participants are asked to enter their scientific domain at the end of the document. It is also possible to leave your name, institution and e-mail address but there is no obligation to do so. This survey does not contain any trackers, please make sure to press the "submission" button in order to save your answers.

Table of contents

  1. Standard geometry magnets at the EMFL facilities
  2. Facility magnets with specific experimental access or geometry 
  3. Facility magnets with specific time dependence 
  4. Mobile installations 

PART 1 :  STANDARD GEOMETRY MAGNETS AT THE EMFL FACILITIES

CATEGORIES

  • DC Magnets : 30-60 T
  • Pulsed magnets: 60 - 100 T with 10-100 ms duration
  • Megagauss magnets > 100 T with sub-millisecond duration
SKIP THIS CATEGORY

DC Magnets: 30 - 60 T 

Required maximum field

30 - 40 T
40 T - 50 T
> 50 T

Additional information

  • 30-40 T: target range for standard resistive or superconducting user magnets with normal access capacity.
  • 40-50 T: target range of current hybrid projects; limited access capacity for users (1 magnet per facility).
  • > 50 T: possible future project requiring a multi-national effort; limited access capacity for users (1 or 2 magnets worldwide).

Required temperature

> 350 K
1.5 - 350 K
< 1.5 K

Required sample space

< 8 mm
8 - 15 mm
15 - 25 mm
> 25 mm

Additional information

Specifications for sample space and temperature are used to estimate the smallest winding / bore diameter that the magnet can have. If you are not sure about sample space, please use the comment box below to let us know about the experiments you want to perform.

Special requirements

Homogeneity
Very low noise
Fast ramping
Persistent mode operation

Tell us more about... 

  • ... the type(s) of experiment(s) you intend to perform with DC magnets with standard geometry ;
  • ... specifications for homogeneity, noise level, fast ramping, persistent mode operation (if applicable) ;
  • ... any other requirement for this class of magnets.

Pulsed Magnets : 60 - 100 T with 10 - 100ms duration

Required maximum field

60 - 70 T
70 - 90 T
> 90 T

Additional information

  • 60-70 T: standard monolithic magnets with smooth profile (sinusoidal rise, exponential decay) in the 100 ms range.
  • 70-90 T: multi-coil magnets with ∼10 ms useful pulse duration around Bmax ; the superposition of pulses from nested magnets creates discontinuities in B(t).
  • >90 T: multi-coil magnets with ∼10 ms useful pulse duration around Bmax ; the superposition of pulses from nested magnets creates discontinuities in B(t) (kinks) and dB/dt (jumps); shots above 90 T may require special justification to protect coils from unnecessary fatigue.

Required temperature

> 350 K
1.5 - 350 K
< 1.5 K

Required sample space

< 5 mm
5 - 10 mm
> 10 mm

Additional information

Specifications for sample space and temperature are used to estimate the smallest winding / bore diameter that the magnet can have. If you are not sure about sample space, please use the comment box below to let us know about the experiments you want to perform.

Special requirements

Homogeneity
Short pulse < 10 ms
Long pulse > 100 ms

Additional information

Short- and long-pulse magnets are important for certain measurements where dB/dt is either beneficial (e.g. inductive measurements) or problematic (e.g. specific heat). Note that longer pulse durations result in substantially longer cool-down times.

Tell us more about...

  • ... the type(s) of experiment(s) you intend to perform in pulsed magnets with standard geometry ;
  • ... specifications for homogeneity or pulse duration (if applicable) ;
  • ... any other requirements for this class of magnets.

Megagauss magnets: > 100 T with sub-millisecond duration

Required maximum field

100-120 T, 100 µs
150-200 T, 10 µs
800-1000 T, 10 µs

Additional information

  • 100-120 T, 100 µs: possible future non-destructive insert-outsert type magnet ; the development would requires investments in both new coils and generators.
  • 150-200 T, 10 µs: disposable single-turn coils ; possibility to perform repeated measurements with specific experimental techniques (VIS-MIR optics, magnetization).
  • 1000 T, 10 µs: electromagnetic flux compression at the ISSP Kashiwa ; integration into the EMFL user access scheme under discussion ; single-shot experiments only.
All magnets are limited in bore diameter to less than 10 mm.

Required temperature

> 350 K
1.5 - 350 K
< 1.5 K

Tell us more about...

  • ... the type(s) of experiment(s) you intend to perform in Megagauss fields ;
  • ... your technical requirements for these experiments.

PART 2 : FACILITY MAGNETS WITH SPECIFIC EXPERIMENTAL ACCESS OR GEOMETRY

CATEGORIES

  • Magnets with extra-wide bore
  • Transverse-access magnets (split coils)
  • More magnets with specific experimental access or geometry
SKIP THIS CATEGORY

Magnets with extra-wide bore

Field-bore preference for DC wide-bore magnets

8.5 T in 800 mm
12 T in 600 mm
17.5 in 370 mm
25 T in 130 mm
35 T in 50 mm

Additional information

Indicate here the maximum field and the room temperature bore diameter that are closest to your needs. (The room-temperature bore takes into account space occupied by equipment used for cooling the magnet but not any cryostats or furnaces necessary for the experiment.) Magnets with 370, 600 and 800 mm refer to the possible use of the outer coils of hybrid magnet systems that are currently under construction ; other magnets would require separate developments ; a magnet producing 30 T in 50 mm bore exists.

Field-bore preference for pulsed wide-bore magnets 

25 T in 350 mm
40 T in 200 mm
50 T in 100 mm
60 T in 50 mm

Additional information

Indicate here the maximum field and the room-temperature bore diameter that are closest to your needs. (The room-temperature bore takes into account space occupied by equipment used for cooling the magnet but not any cryostats or furnaces necessary for the experiment.). Note that pulsed wide-bore magnets have longer pulse durations (>100 ms) and substantially longer cool-down times.

Tell us more about...

  • ... the type(s) of experiment(s) you want to perform with wide-bore magnets ;
  • ... any other requirements for this class of magnets.

Transverse-access magnets (split coils)

Importance rating

DC, 20-25 T
Pulsed, 50-55 T

Additional information

Rate here the importance of this type of magnet for your research.

Required temperature

> 350 k
1.5 - 350 k

Preferred field-bore-split optimization for DC magnets

N : Go for more field, less bore
S : Go for more bore, less field
E : Go for more field, less split
W : Go for more split, less field

Additional information

The center of the wind rose contains a likely compromise of parameters for a DC split coil. Indicate in which direction the parameters in the center of the wind rose for DC magnets should be changed in order to suit your needs (for example, indicate N and E to obtain more field in exchange for a reduced bore and/or split).
N : Go for more field, less bore
S : Go for more bore, less field
E : Go for more field, less split
W : Go for more split, less field

Additional information

The center of the wind rose contains a likely compromise of parameters for a pulsed split coil. Indicate in which direction  and to what degree  the parameters should be changed in order to better suit your needs (for example, indicate N and E to obtain more field in exchange for a reduced bore and/or split).

Tell us more about...

  • ...the type(s) of experiment(s) you intend to perform with split-coils (DC or pulsed);
  • ...specifications for the required experimental access and sample space ;
  • ...any other requirements for this class of magnets.

More magnets with specific experimental access or geometry

More possibilites...

Conical bore magnet: pulsed or DC magnet with up to 30◦ opening angle of the bore.

Levitation magnet/large gradient magnet: magnet designed to optimize the volume both the magnetic field and its gradient are simultaneously large

Dipole magnet: accelerator-type magnet designed to extend the lateral distance over which a substantial perpendicular field is obtained (see figure on the right).

Additional information

Note that special magnet geometries imply substantially lower fields than those available in conventional magnets.

Tell us more about...

  • ... your technical requirements for the listed magnets ;
  • ... specifications for the specific experimental access and geometry  ;
  • ...the type(s) of experiment(s) you want to perform with them and other possible comments.

PART 3 : FACILITY MAGNETS WITH SPECIFIC TIME DEPENDENCE 

CATEGORIES

  • DC outsert, pulsed insert
  • Flat-top pulsed magnets
  • More magnets with specific time dependence
SKIP THIS CATEGORY

DC outsert, pulsed insert

Required total maximum field (DC & pulsed) 

<50 T
>50 T

Additional information

DC-outsert-pulsed-insert magnets are useful for applications requiring pre-polarization or the alignment of magnetic sub-systems.

Required DC background field

< 10 T
> 10 T

Required temperature

> 350 K
1.5 - 350 K
< 1.5 K

Required sample space

< 5 mm
5 - 10 mm
> 10 mm

Additional information

Specifications for sample space and temperature are used to estimate the smallest winding / bore diameter that the magnet can have. If you are not sure about sample space, please use the comment box below to let us know about the experiments you want to perform.

Tell us more about...

  • ... the type(s) of experiment(s) you intend to perform in DC-outsert, pulsed-insert magnets ;
  • ... any other requirements for this class of magnets.

Flat-top pulsed magnets

Required peak field and plateau width

40 T for 20-50 ms
50 T for 10-20 ms
60 T for 5-10 ms

Additional information

Flat-top magnets provide a plateau with typically ≃1% flatness for constant-field measurements ; implementing a flat-top magnet requires substantial infrastructure investments for developing an auxiliary capacitor bank and inductive coupler.

Required temperature

>350K
1.5 -350 K
< 1.5 T

Required sample space

< 5mm
5-10 mm
>10 mm

Additional information

Specifications for sample space and temperature are used to estimate the bore diameter. If you are not sure about sample space, please use the comment box below to let us know about the experiments you want to perform.

Special requirements

Homogeneity
Enhanced flatness < 1%

Tell us more about...

  • ... the type(s) of experiment(s) you intend to perform in flat-top pulsed magnets;
  • ... specifications for homogeneity and flatness (if applicable) ;
  • ... any other requirements for this class of magnets.

More magnets with specific time dependence

More possibilities

Oscillating-field magnet: pulsed magnet driven by a generator resembling a serial RLC circuit ; field reversals of 80-95% between the first and second maximum are feasible depending on bore diameter, pulse duration and peak field ; reducing either parameter also reduces the decay ; technical development requiring additional investments due to the need of capacitors with enhanced tolerance towards voltage reversal.

Slow-start magnet: pulsed magnet providing a smoother onset of the magnetic field in order to reduce eddy currents, noise and heating effects associated with the initial rise.

Tell us more about...

  • ... your technical requirements for oscillating-field magnets;
  • ...your ideas for more magnets with specific time-dependence;
  • ...the type(s) of experiment(s) you want to perform and other possible comments.

PART 4 : MOBILE INSTALLATIONS 

CATEGORIES

  • Mobile infrastructure specifications
  • Mobile magnets for uses outside the EMFL facilities
SKIP THIS CATEGORY

Mobile infrastructure specifications

Preferred infrastructure size

Conventional pulsed generator
Upscaled pulsed generator
Downscaled pulsed generator

Additional information

  • Conventional pulsed generator: 30-60 T depending on coil type in ≃20 mm, ≃10 ms ; one shot at full field approximately every 10 minutes ; pallet-sized modules requiring 12-15 m2 in the host facility ; 24 kV operating voltage and possible violent coil failures.
  • Upscaled installations: larger useful volumes, large pulse duration, smaller duty cycle ; installation mounted in containers that have to be stored at, or connected to, the measurement site ; enhanced security requirements due to the additional stored energy.
  • Downscaled installations: higher duty cycle, less pulse duration for a useful diameters <5 mm ; installation mounted on a single pallet.

Alternative installations

Megagauss generator
Superconducting system

Additional information

Mobile Megagauss generators provide 100 T in 8 mm / 5 µs approximately once every hour ; installation mounted on a single pallet; enhanced security requirements due to the use of 50-60 kV and the coil explosion ; provisions for electromagnetic shielding and evacuating metallic vapors necessary.

Tell us more about...

  • ... the type(s) of experiment(s) you intend to perform with a mobile generator;
  • ...the type of facility where the experiment would be installed;
  • ...any other requirements for mobile generators.

Mobile magnets for uses outside the EMFL facilities

Required coil geometry

Standard solenoid
Horizontal bore
Bi-conical bore
Split coil

Required temperature

> 350 K
1.5 - 350 K
< 1.5 K

Required sample space

< 5 mm
5-10 mm
> 10 mm

Special requirements

Variable coil orientation
Advanced vibration damping
UHV comptability

Tell us more about...

  • ... the type(s) of experiment(s) you intend to perform with mobile magnets ;
  • ... the type of facility where the experiment would be installed ;
  • ... why your experiment requires a special coil-geometry (if applicable) ;
  • ... specifications for coil orientation, vibration damping or UHV compatibility (if applicable) ;
  • ... any other requirement for this class of magnets.

FINAL INFORMATION

If you are willing to help us further in establishing this road map, we suggest you to leave your contact details. We will only contact you to obtain further precisions regarding your needs in terms of magnet technology and will not distribute any personal information outside this project.

Please do not forget to press the submit button below to save your answers.

Thank you for participating in this survey !

Thank you for your participation! Your form has been submitted successfully.
There was an error trying to send the form. Please try again and be patient after sumitting >5s.