[Spm] Re: MFM phase shift (Yongsunthon, Ruchirej)
van Schendel Pieter
schendel at nanosurf.com
Thu Feb 28 09:55:18 EST 2008
It is a little bit hard to answer this question if you don't specify what model for tip and sample you have used. I assume you used the following model:
If both the tip and the sample are magnetically hard, the force acting on the tip is proportional to the convolution integral of the sample field and the magnetic charge density on the tip (magnetic charge density being proportional to the divergence of the magnetization).
In dynamic mode you measure the force derivative. If both the tip and the sample are magnetically hard (i.e. independent of z), the force derivative can be obtained from the convolution integral of the sample field derivative and the magnetic charge density of on the tip.
The field of a magnetic point dipole decays with 1/r^3, the field of an infinitely long current carrying conductor decays with 1/r (Ruchi's model ?).
If the tip is also a point dipole, the convolution integral becomes equivalent to differentiating the sample field at the position of the dipole in the direction of the dipole. Thus, the force derivative between two dipoles aligned along z will decay with 1/z^5, the force derivative between a current carrying line and a point dipole will decay with 1/z^3.
You can get other relations when:
- The tip or the sample change their magnetization when you come close to the sample: are you sure the nanoparticle is magnetically hard?
- The tip is not well modeled by a point-dipole. This is generally not the case, so you have to take this into account.
As a first step, you can replace the point dipole by an extended dipole (infinitely thin bar magnet). Then the convolution integral changes from a derivative to the difference of the field at location of the two poles. If the second pole is very far away from your sample, the field there will be close to zero, and you effectively get the force on an 'unphysical' monopole, which is proportional to the field instead of the field derivative, so you loose one derivative.
If you take into account that the magnetic charges in actual tips are distributed over a much larger volume, the decay of the force will be even slower. You loose the second derivative when you assume that you actually have a semi-infinitely extended line charge going away from the tip apex( this is more-or-less accurate for a triangular tip coating).
- The structure is periodic: when you are far away from the sample, the force will decay exponentially with the distance divided by the wavelength. Do you have single nanoparticles or an array of nanoparticles?
If Ruchi's remark about the linearity of the Phase output holds, you also have to may also have to take into account that the phase shift is only proportional to the force derivative when the phase shift is not large.
Pieter van Schendel
-----Original Message-----
From: spm-bounces at spmlist.di.com [mailto:spm-bounces at spmlist.di.com] On Behalf Of spm-request at spmlist.di.com
Sent: Thursday, February 28, 2008 10:35 AM
To: spm at spmlist.di.com
Subject: Spm Digest, Vol 43, Issue 14
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Today's Topics:
1. RE: Multimode PSD spectral response (Raoul Enning) (Poyet Benoit)
2. force spectroscopy proteins (Ronnie Willaert)
3. Re: MFM phase shift (Yongsunthon, Ruchirej)
----------------------------------------------------------------------
Message: 1
Date: Wed, 27 Feb 2008 10:02:46 +0100
From: "Poyet Benoit" <Benoit.Poyet at lne.fr>
Subject: [Spm] RE: Multimode PSD spectral response (Raoul Enning)
To: <spm at spmlist.di.com>
Message-ID:
<CB10695776A93042BFF1D37123973548037E677B at TRAMSG.intra.lne>
Content-Type: text/plain; charset="iso-8859-1"
Dear MrEnning,
I'm developping a metrologcal AFM and I would like to use a SLED for the cantilever deflexions optical detection.... What kind of sled do you use ?
Thanks for your help.
Benoit Poyet
-----Message d'origine-----
De : spm-bounces at spmlist.di.com [mailto:spm-bounces at spmlist.di.com]De la part de spm-request at spmlist.di.com Envoyé : mardi 26 février 2008 10:53 À : spm at spmlist.di.com Objet : ***SPAM***[Score/Req: 08.1/5.0] Spm Digest, Vol 43, Issue 12
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Today's Topics:
1. smoke particules analysis with AFM (Ducourtieux S?bastien)
(dipak paramanik)
2. Meeting Announcement: DNA-Based Nanodevices (May 29-31, Jena,
Germany) (Wolfgang Fritzsche)
3. Re: smoke particules analysis with AFM (Ducourtieux
S?bastien) (Joel Pikarsky)
4. RE: Spm Digest, Vol 43, Issue 10 (Singh, Seema)
----------------------------------------------------------------------
Message: 1
Date: Sat, 23 Feb 2008 12:37:09 +0000 (GMT)
From: dipak paramanik <dipak1205 at yahoo.co.in>
Subject: [Spm] smoke particules analysis with AFM (Ducourtieux
S?bastien)
To: spm at spmlist.di.com
Message-ID: <699576.6881.qm at web8614.mail.in.yahoo.com>
Content-Type: text/plain; charset="iso-8859-1"
Atomically flat Mica surface could be the best one.
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Today's Topics:
1. Multimode PSD spectral response (Raoul Enning)
2. smoke particules analysis with AFM (Ducourtieux S?bastien)
----------------------------------------------------------------------
Message: 1
Date: Fri, 22 Feb 2008 15:20:10 +0100
From: Raoul Enning
Subject: [Spm] Multimode PSD spectral response
To: spm at spmlist.di.com
Message-ID: <47BEDA1A.6060500 at nano.mavt.ethz.ch>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hello everyone,
Is there anyone that knows what the Spectral responsivity of the PSDs in the Multimode-2 AFMs are? I am trying to modify the head, and replace the laser with an SLED. I need to know what the best wavelength for the PSD would be. Is there anything else I need to consider besides the spectral response of the psd? Thanks for the help!
Regards,
Raoul Enning
------------------------------
Message: 2
Date: Fri, 22 Feb 2008 17:32:10 +0100
From: Ducourtieux S?bastien
Subject: [Spm] smoke particules analysis with AFM
To:
Message-ID:
Content-Type: text/plain; charset="iso-8859-1"
Dear AFM users
We are starting a new study concerning the morphology determination of particules coming from material combustions. We want to use AFM to image those particules that we expect to be very small (nanoparticules). First of all we want to deposite those particules using a very flat surface that we would introduce directly into the smoke. What kind of surface would you recommend me ? Does someone already try this ? I'm open to anykind of information or advice that could help me to start this study.
Thanking you in advance
Sébastien Ducourtieux
***********************************************************************
Laboratoire national de métrologie et d'essais
CSMI 338 - Unité Nanometrologie Dimensionnelle Z.A. de Trappes-Elancourt 29, avenue Roger Hennequin
78197 Trappes Cedex
http://www.lne.fr
tel : 33 1 30 69 21 84
fax : 33 1 30 16 28 41
***********************************************************************
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End of Spm Digest, Vol 43, Issue 11
***********************************
Dipak Paramanik
Doctoral Scholar
XPS/SPM Laboratory
Istitute of Physics
Bhubaneswar -751005
India
Personal homepage:
http://www.iopb.res.in/~dipakpk
---------------------------------
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Message: 2
Date: Mon, 25 Feb 2008 09:08:13 +0100
From: Wolfgang Fritzsche <fritzsche at ipht-jena.de>
Subject: [Spm] Meeting Announcement: DNA-Based Nanodevices (May 29-31,
Jena, Germany)
To: spm at spmlist.di.com
Message-ID: <945C9714-2A7E-479E-9AE5-9AB10E5233E8 at ipht-jena.de>
Content-Type: text/plain; charset="us-ascii"
DNA-Based Nanodevices
May 29-31, 2008
IPHT Jena (Germany)
http://www.ipht-jena.de/dna.html
abstract deadline: March 1st, 2008
__________________
Dr. Wolfgang Fritzsche
Institute of Photonic Technology (IPHT)
Nanobiophotonics Department
PO Box 100 239, 07702 Jena, Germany
Tel. +49-(0)3641-206304, Fax: -206344
fritzsche at ipht-jena.de http://www.ipht-jena.de/ DNA-Based Nanodevices May 29-31, 2008 IPHT Jena www.ipht-jena.de/ dna.html
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Message: 3
Date: Mon, 25 Feb 2008 10:30:56 -0500
From: Joel Pikarsky <joel.pikarsky at mirc.gatech.edu>
Subject: [Spm] Re: smoke particules analysis with AFM (Ducourtieux
S?bastien)
To: spm at spmlist.di.com
Message-ID: <47C2DF30.1090001 at mirc.gatech.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Mica would be my first thought.
Flat, cheap, temperature resistant, and you can cut to any size or shape
you want.
Search the SPM archives for important posts on buying and cutting Mica.
Joel Pikarsky
"Scourge of the Cleanroom"
> 2. smoke particules analysis with AFM (Ducourtieux S?bastien)
>
> Subject: [Spm] smoke particules analysis with AFM From: Ducourtieux
> Sébastien <Sebastien.Ducourtieux at lne.fr> Date: Fri, 22 Feb 2008
> 17:32:10 +0100 To: <spm at spmlist.di.com>
>
> To: <spm at spmlist.di.com>
>
>
> Dear AFM users
>
> We are starting a new study concerning the morphology determination
> of particules coming from material combustions. We want to use AFM to
> image those particules that we expect to be very small
> (nanoparticules). First of all we want to deposite those particules
> using a very flat surface that we would introduce directly into the
> smoke. What kind of surface would you recommend me ? Does someone
> already try this ? I'm open to anykind of information or advice that
> could help me to start this study.
>
> Thanking you in advance
>
> Sébastien Ducourtieux
>
> ***********************************************************************
> Laboratoire national de métrologie et d'essais
>
> CSMI 338 - Unité Nanometrologie Dimensionnelle Z.A. de
> Trappes-Elancourt 29, avenue Roger Hennequin 78197 Trappes Cedex
> http://www.lne.fr
>
> tel : 33 1 30 69 21 84 fax : 33 1 30 16 28 41
> http://www.veeco.com/library/community_type.php?type_id=2amp;sub_id=2amp;tech_sub_id=1
------------------------------
Message: 4
Date: Fri, 22 Feb 2008 16:32:41 -0700
From: "Singh, Seema" <seesing at sandia.gov>
Subject: [Spm] RE: Spm Digest, Vol 43, Issue 10
To: "spm at spmlist.di.com" <spm at spmlist.di.com>
Message-ID:
<FB940EFAA28AA148A702736CD2BE303E02682E8526 at ES01SNLNT.srn.sandia.gov>
Content-Type: text/plain; charset=us-ascii
Postdoctoral Job opening at Sandia National Laboratory, Livermore, CA
We are looking for candidates with prior experience in investigation of solid-liquid interface using probe microscopy and dynamic and static force spectroscopy with strong theoretical background. The candidates will have a strong publication record, good communication skills and be self motivated. Previous research experience in using second order nonlinear optical techniques like SFG, and neutron reflectivity, surface potential and electrostatic force measurement is highly desirable.
If interested, please contact Dr. Seema Singh at seesing at sandia.gov or (925) 294 4551. This position is also open at sandia.gov external website.
________________________________________
From: spm-bounces at spmlist.di.com [spm-bounces at spmlist.di.com] On Behalf Of spm-request at spmlist.di.com [spm-request at spmlist.di.com]
Sent: Thursday, February 21, 2008 1:29 AM
To: spm at spmlist.di.com
Subject: Spm Digest, Vol 43, Issue 10
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Today's Topics:
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Robinson) (Phil Kaszuba)
----------------------------------------------------------------------
Message: 1
Date: Wed, 20 Feb 2008 13:14:09 +0000 (GMT)
From: dipak paramanik <dipak1205 at yahoo.co.in>
Subject: [Spm] AFM Purchase
To: spm at spmlist.di.com
Message-ID: <882949.82256.qm at web8601.mail.in.yahoo.com>
Content-Type: text/plain; charset="iso-8859-1"
NT_MDT AFM are made in Russia.
There are few users of this instrument in USA.
There are some institutions in India under Atomic energy.
These institutes can not buy AFM form USA due to Indo-US international policy.
So, they buy AFM form Russia or other countries. You will find NT_MDT system
in many atomic energy institution in india.
However I feel Digital (Veeco) system is much better that NT_MDT system in all respect.
Best Regards
Dipak Paramanik
Doctoral Research scholar
IoP, Bhubaneswar
http:\\www.iopb.res.in\~dipakpk
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Today's Topics:
1. AFM Purchase (Ted Robinson)
2. Users feedback from Veeco?s diInnova AFM
(Jos? Jes?s Ben?tez Jim?nez)
3. Re: Poly Grain Size (Alexander S. Filonov)
4. UKSPM 2008 (Wilson, Neil)
5. Re: Spm Digest, Vol 42, Issue 3 (Pablo Ares)
6. AFM (Vishal Gupta)
----------------------------------------------------------------------
Message: 1
Date: Fri, 8 Feb 2008 06:40:18 -0500
From: Ted Robinson
Subject: [Spm] AFM Purchase
To:
Message-ID:
Content-Type: text/plain; charset="iso-8859-1"
I am a post doc at the University of Vermont. We are in the process of evaluating several afms. We are having a hard time finding anyone in the US that uses the NT-MDT system. Can any one give any comments. This is greatly speed up our evaluation process.
Thanks!
_________________________________________________________________
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Message: 2
Date: Fri, 15 Feb 2008 11:36:02 +0100
From: Jos? Jes?s Ben?tez Jim?nez
Subject: [Spm] Users feedback from Veeco?s diInnova AFM
To:
Message-ID: <000301c86fbe$8fbbfb70$3c9a6fa1 at cartuja.csic.es>
Content-Type: text/plain; charset="iso-8859-1"
Hi everybody!.
I am in the process of purchasing a new AFM and the diInnova model is one of
the options for the kind of research I would like to carry on. I am running
out of references about this new AFM and I would really appreciate some
feedback from dedicated users. One of my concerns is about its flexibility
on managing input and output signals (a key point in their bronchure). I
would be also very helpful to get the opinion from someone using both a
multimode and the new Innova.
As this may be considered as personal opinions I may recommend to contact me
out of the general list.
Thanks
J.J. Ben?tez
Instituto de Ciencia de Materiales de Sevilla
CSIC-Universidad de Sevilla
Avda. Americo Vespucio 49
Isla de la Cartuja
41092 Sevilla
Spain
email: benitez at icmse.csic.es
tel. 34 95 448 9551
fax. 34 95 446 0665
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Message: 3
Date: Sat, 26 Jan 2008 15:49:06 +0300
From: "Alexander S. Filonov"
Subject: [Spm] Re: Poly Grain Size
To: "SPM DI list"
Message-ID: <20080126123954.M34847 at mail.genebee.msu.ru>
Content-Type: text/plain; charset=koi8-r
Dear Stephen Rothwell,
we have a function "Enum Features" in our software "FemtoScan Online", which
may be is what you need. It can calculate different parameters of individual
grains (such as square, volume, perimeter etc.) and put them in one table. Try
it from our web site: http://www.nanoscopy.net/en/Femtoscan-D.php
--
Open WebMail Project (http://openwebmail.org)
------------------------------
Message: 4
Date: Mon, 18 Feb 2008 08:31:15 -0000
From: "Wilson, Neil"
Subject: [Spm] UKSPM 2008
To:
Message-ID:
<7363ACF6765958459F9FD54410108A4856C6A2 at HOLLY.ads.warwick.ac.uk>
Content-Type: text/plain; charset="windows-1250"
Dear Scanned Probe Microscopist,
Once again this summer UKSPM will be held in London (25-26th June) as part of the MICROSCIENCE conference organized by the Royal Microscopical Society. As usual, UKSPM will provide an opportunity to present to, and interact with, fellow scanned probe microscopists from a broad spectrum of fields. It promises to be a fascinating event with a great line-up of invited speakers, the all important UKSPM dinner where the serious business of socializing can be attended to, and of course the associated trade show where the latest instrument developments will be showcased.
The submission deadline for abstracts for oral presentations is approaching soon (February the 29th). We welcome abstracts from all disciplines utilizing and advancing SPM. Alongside more experienced speakers we are keen to promote opportunities for early career researchers, from PhD students to Postdocs and young academics, and hope to have industry sponsored prizes for oral and poster presentations in these categories.
We look forward to seeing you in June, and if you have any enquiries please see the UKSPM website (link below), or feel free to contact myself (Neil Wilson) about the scientific programme or Kirsty Grimwade of the RMS (see UKSPM website) about organizational matters.
Best wishes,
Neil
www.microscience2008.org.uk/UKSPM
p.s. Limited subsidized accommodation is available on a first come first served basis so you are advised to register as soon as possible!
_____________________________________
Dr Neil Wilson
Physics Department
University of Warwick
Coventry
CV4 7AL
UK
HYPERLINK "http://go.warwick.ac.uk/microscopy/staff/nw"http://go.warwick.ac.uk/microscopy/staff/nw
Office +44 (0)24 765 24168
Lab +44 (0)24 765 74476
_____________________________________
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Message: 5
Date: Wed, 09 Jan 2008 13:02:02 +0100
From: Pablo Ares
Subject: [Spm] Re: Spm Digest, Vol 42, Issue 3
To: spm at spmlist.di.com
Message-ID: <200801091108.m09B8YsV014094 at outgoing.veeco.com>
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------------------------------
Message: 6
Date: Thu, 14 Feb 2008 21:56:14 -0800 (PST)
From: Vishal Gupta
Subject: [Spm] AFM
To: spm at spmlist.di.com
Message-ID: <315008.86957.qm at web25913.mail.ukl.yahoo.com>
Content-Type: text/plain; charset="iso-8859-1"
Dear AFM users,
I have few question regarding PicoScan (Agilent) and I believe those apply to Nanoscope (Veeco) users as well:
1. I am using plain glass slide for imaging with triangular beam cantilever (0.12 N/m) in contact mode. While aligning laser on cantilever, I am seeing multiple reflection of laser on video monitor with same intensity. So its hard to tell which laser spot is real and which is image on glass surface. Any suggestion to solve this issue.
2. While doing the force measurement, I set the force set point as zero. But changing the force set point to higher positive value shift the force curve vertically down and changing the force set point to higher negative value shift the curve vertically upward. what does that mean and what value should I use for force set point. Any thumb rule or suggestion would help.
Hope to hear from you.
Greetings,
Vishal
---------------------------------
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End of Spm Digest, Vol 43, Issue 9
**********************************
Dipak Paramanik
Doctoral Scholar
XPS/SPM Laboratory
Istitute of Physics
Bhubaneswar -751005
India
Personal homepage:
http://www.iopb.res.in/~dipakpk
---------------------------------
Explore your hobbies and interests. Click here to begin.
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Message: 2
Date: Wed, 20 Feb 2008 09:06:13 -0500
From: Phil Kaszuba <pkaszuba at us.ibm.com>
Subject: [Spm] Re: Spm Digest, Vol 43, Issue 9 - 1. AFM Purchase (Ted
Robinson)
To: spm at spmlist.di.com
Message-ID:
<OF63A01E96.6553CCE5-ON852573F5.004C62A2-852573F5.004D8B6F at us.ibm.com>
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***********************************
------------------------------
Message: 2
Date: Wed, 27 Feb 2008 14:41:59 +0100
From: Ronnie Willaert <ronnie.willaert at vub.ac.be>
Subject: [Spm] force spectroscopy proteins
To: spm at spmlist.di.com
Message-ID: <72BD2D21-9E64-4BBF-969B-9F9618B87E66 at vub.ac.be>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
Hi all,
We have a Di Multimode Nanoscope IIIa AFM and would like to perform
force spectroscopy on proteins (i.e. interaction force of protein
and
ligand and protein unfolding experiments). Veeco offers the
PicoForce
extension. What's the experience with this module?
Are there cheaper alternatives possible? Is the following
combination
also a good alternative?: PCM-90 AFM Probe Calibration Module from
Novascan in combination with a closed-loop scanner from Veeco.
Thanks in advance for the suggestions!
Best regards,
Ronnie Willaert (VUB, Belgium)
------------------------------
Message: 3
Date: Wed, 27 Feb 2008 19:22:48 -0500
From: "Yongsunthon, Ruchirej" <YongsuntR at corning.com>
Subject: [Spm] Re: MFM phase shift
To: spm at spmlist.di.com
Message-ID:
<7D29753ADD2B0B42930119A5E4AE8D100151DDD9 at CVCV0XI05.na.corning.com>
Content-Type: text/plain; charset="us-ascii"
In regard to the question on the SPM forum about the z dependence of
phase shifts, the theory for a perfect dipole suggests that delta(phi) ~
d2B/dz2. I have found that signal looks much more like B, not the
second derivative of B (so roughly a 1/z dependence). Many have come up
with the "monopole" model of the magnetic tip to explain such
observations, even though magnetic monopoles are unphysical. In the
past, I have chosen to explain the apparent 1/z dependence as a tip
convolution effect. The measured signal is the integral of the phase
over the entire tip volume, which takes out at least one derivative. I
had reasoned out the other 1/z but can't currently recall the rest of
the argument. For my past research, I used to calibrate on metallic
lines (theoretical response easily calculated) to determine an
instrumental response function and then used this response in a Maximum
Entropy Deconvolution routine to determine the "true" phase response.
As for the signal linearity, standard DI/Veeco systems output "phase" ,
but only the NS4 or higher controllers output true phase. If you are
using the (older) analog Extender Box, then your output is actually
sin(phase). The units are not true degrees but "boceks", the informal
name in honor of the guy who designed the simple circuit that outputs
the phase response. Although boceks are not degrees, they are close for
small phase shifts (good enough). If you are using a non-DI system, I'm
not sure what the output quantity is.
I have not done MFM in a long time but feel free to contact me if you'd
like access to any PDFs of my past work (quantitative MFM on
current-carrying metallic lines to determine current density with
sub-micron resolution).
Sincerely,
Ruchi
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