Stiff cantilever AFM - Revision history

Apm at 18:05, 29 March 2026

2026-03-29T18:05:22Z

← Older revision		Revision as of 20:05, 29 March 2026
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	* [https://de.wikipedia.org/wiki/Franz_Josef_Gie%C3%9Fibl Franz Josef Gießibl] (de)		* [https://de.wikipedia.org/wiki/Franz_Josef_Gie%C3%9Fibl Franz Josef Gießibl] (de)
	* [https://de.wikipedia.org/wiki/Leo_Gross_(Physiker) Leo Gross (Physiker)] (de)		* [https://de.wikipedia.org/wiki/Leo_Gross_(Physiker) Leo Gross (Physiker)] (de)

			[[Category:Direct path]]

Apm: /* A historic naming accident */

2026-03-27T17:39:01Z

A historic naming accident

← Older revision		Revision as of 19:39, 27 March 2026
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	The contact vs non-contact distinction (now with the bi-stable snap gone) makes no longer 100% sense. <br>		The contact vs non-contact distinction (now with the bi-stable snap gone) makes no longer 100% sense. <br>
	Rather more sensible would be to distinguish non-contact from contact by the switch from <br>		Rather more sensible would be to distinguish non-contact from contact by the switch from <br>
	attractive forces to repulsive forces. Roughly meaning the distance where one crosses under the vdW radii of atoms. <br>		attractive forces to repulsive forces. Roughly meaning the distance where one crosses under the vdW radii of atoms getting Pauli repulsion dominating. <br>
	Now we sometimes have a situation where we clearly are within the Pauli-repulsive-regime <br>		Now we sometimes have a situation where we clearly are within the Pauli-repulsive-regime <br>
	(which is as much contact as one can possibly get) yet still the technique is named non-contact. <br>		(which is as much contact as one can possibly get) yet still the technique is named non-contact. <br>

Apm: /* Force measurement method */

2026-03-27T17:37:23Z

Force measurement method

← Older revision		Revision as of 19:37, 27 March 2026
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	Another difference between old and new: <br>		Another difference between old and new: <br>
	– old nc-AFM (an c-AFM) used deflection of a laser and a four quadrant photo-diode <br>		– old nc-AFM (an c-AFM) used deflection of a laser and a four quadrant photo-diode <br>
	– new nc-AFM measures detuning of resonant frequency (frequency shift) <br> time can be measures especially precisely so this helps <br> '''Rarely it's called FM-AFM for frequency modulation.'''		– new nc-AFM measures detuning of resonant frequency (frequency shift) of a quartz tuning fork <br> time can be measures especially precisely so this helps <br> '''Rarely it's called FM-AFM for frequency modulation.'''

	=== A historic naming accident ===		=== A historic naming accident ===

Apm: /* old nc-AFM ~vs~ new nc-AFM */ improvements & typo-fixes

2026-03-27T17:36:10Z

old nc-AFM ~vs~ new nc-AFM: improvements & typo-fixes

← Older revision		Revision as of 19:36, 27 March 2026
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	led to a bi-stable snap to the surface. <br>		led to a bi-stable snap to the surface. <br>
	– either these forces pressed the tip to the surface making it scratch over the surface quite roughly (contact mode) <br>		– either these forces pressed the tip to the surface making it scratch over the surface quite roughly (contact mode) <br>
	– or the tip was so far away from the surface that subatomic resolution was not ~~posible~~ either (non-concact nc mode) <br>		– or the tip was so far away from the surface that subatomic resolution was not possible either (non-concact nc mode) <br>
	~~Noting~~ in-between the two due to the bi-stable snap-to surface. <br>		Nothing in-between the two due to the bi-stable away from surface and snap-to surface states. <br>

	With the introduction of stiffer cantilevers the bi-stable snap could finally be avoided <br>		With the introduction of stiffer cantilevers the bi-stable snap could finally be avoided <br>

Apm: /* Atomic stiffness microscopy "ASM"? */ some cleanup

2026-03-27T17:34:43Z

Atomic stiffness microscopy "ASM"?: some cleanup

← Older revision		Revision as of 19:34, 27 March 2026
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	What is actually imaged with the (unaltered as-is) frequency shift signal <br>		What is actually imaged with the (unaltered as-is) frequency shift signal <br>
	is actually the over the amplitude averaged stiffness rather than the force. <br>		is actually the over the amplitude averaged stiffness rather than the force. <br>
	So AFM is seems like ~~a bit of~~ a misleading misnomer. <br>		So AFM seems like a misleading misnomer. <br>
	Reasons for the naming being historic. <br>		Reasons for the naming being historic. <br>
	For small amplitude ~~that is~~ the signal corresponds ~~better~~ to the local stiffness at center of oscillations. <br>		For small amplitude the signal corresponds roughly to the local stiffness at center height of oscillations. <br>

	There is a way to extract force information via some methods including Sader Jarvis formula and Gießibl matrix method. <br>		There is a way to extract force information via some methods including Sader Jarvis formula and Gießibl matrix method. <br>
	{{wikitodo\|Find out enough to understand and explain this magic seeming "finding forces from local stiffnesses" process.}} <br>		{{wikitodo\|Find out enough to understand and explain this magic seeming "finding forces from local stiffnesses" process. It is not simple integration here.}} <br>
	[https://www.beilstein-journals.org/bjnano/articles/3/27 2012 – Analysis of force-deconvolution methods in frequency-modulation atomic force microscopy]		[https://www.beilstein-journals.org/bjnano/articles/3/27 2012 – Analysis of force-deconvolution methods in frequency-modulation atomic force microscopy]

Apm: /* Related */ big update

2026-01-07T14:32:47Z

Related: big update

← Older revision		Revision as of 16:32, 7 January 2026
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	== Related ==		== Related ==

	* [[Scanning probe microscopy]]		* '''[[Scanning probe microscopy upwards into 3D]]'''
			* '''[[CuOx tip]]''' (no bending & snap-back)
	* [[Snapback]]		* [[Snapback]]
			* [[Mechanosynthesis adapter molecule]]
			* [[Mechanosynthesis mode]]
			----
			* '''[[SPM user interfaces]]'''
			* '''[[Scanning probe microscopy]]'''
			----
			* [[Surface molecular system]]

	== External links ==		== External links ==

Apm: /* Kolibri sensor */ added note on unneccessarily high stiffness

2025-05-05T06:22:29Z

Kolibri sensor: added note on unneccessarily high stiffness

← Older revision		Revision as of 08:22, 5 May 2025
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	Is is again orders of magbitude stiffer than the qPlus sensor. <br>		Is is again orders of magbitude stiffer than the qPlus sensor. <br>
	As it can oscillate in two directions it can detect sidewards forces too not just vertical ones. <br>		As it can oscillate in two directions it can detect sidewards forces too not just vertical ones. <br>
	As it is a newer younger design there may ~~bot~~ yet be as much community knowledge and user experience documentation around. <br>		As it is a newer younger design there may not yet be as much community knowledge and user experience documentation around. <br>
	It seems to come withing a metal housing giving it a significant bigger size compared to qPlus.		It seems to come withing a metal housing giving it a significant bigger size compared to qPlus.

			Unnecessarily high stiffness may make the sensor quite a bit less optimal than qPlus brand sensors.

	{{wikitodo\|Add quantitative details.}}		{{wikitodo\|Add quantitative details.}}

Apm: /* Atomic stiffness microscopy "ASM"? */

2025-05-05T06:19:55Z

Atomic stiffness microscopy "ASM"?

← Older revision		Revision as of 08:19, 5 May 2025
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	is actually the over the amplitude averaged stiffness rather than the force. <br>		is actually the over the amplitude averaged stiffness rather than the force. <br>
	So AFM is seems like a bit of a misleading misnomer. <br>		So AFM is seems like a bit of a misleading misnomer. <br>
	Reasons for the naming being historic.		Reasons for the naming being historic. <br>
	For small amplitude that is the signal corresponds better to the local stiffness at center of oscillations. <br>		For small amplitude that is the signal corresponds better to the local stiffness at center of oscillations. <br>

Apm: added section == Atomic stiffness microscopy "ASM"? ==

2025-05-05T06:18:07Z

added section == Atomic stiffness microscopy "ASM"? ==

@@ Line 5: / Line 5: @@
 '''Stiff cantilever AFM''' generally known as '''(subatomically resolving) nc-AFM''' (rarely FM-AFM) <br>
 is a form of [[scanning probe microscopy]] that probes forces rather than currents.
 == old nc-AFM ~vs~ new nc-AFM ==

Apm: /* A historic naming accident */ Changes reflecting new insight that qPlus is usually operated more in the attractive non-contact regime (but still not always)

2024-07-16T09:31:36Z

A historic naming accident: Changes reflecting new insight that qPlus is usually operated more in the attractive non-contact regime (but still not always)

← Older revision		Revision as of 11:31, 16 July 2024
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	=== A historic naming accident ===		=== A historic naming accident ===

	~~Unfortunately the~~ contact vs non-contact distinction (now with the bi-stable snap gone) makes no longer sense. <br>		The contact vs non-contact distinction (now with the bi-stable snap gone) makes no longer 100% sense. <br>
	Rather more sensible would be to distinguish non-contact from contact by the switch from <br>		Rather more sensible would be to distinguish non-contact from contact by the switch from <br>
	attractive forces to repulsive forces. Roughly meaning the distance where one crosses under the vdW radii of atoms. <br>		attractive forces to repulsive forces. Roughly meaning the distance where one crosses under the vdW radii of atoms. <br>
	Now we ~~often~~ have a situation where we clearly are within the Pauli-repulsive-regime <br>		Now we sometimes have a situation where we clearly are within the Pauli-repulsive-regime <br>
	(which is as much contact as one can possibly get) yet still the technique is named non-contact. <br>		(which is as much contact as one can possibly get) yet still the technique is named non-contact. <br>
	~~Reason for why~~ this page is called stiff cantilever AFM rather than ~~nc-~~AFM.		For this reason this page is called more generally "stiff cantilever AFM" rather than "non contact AFM".

	There is also qPlus and kolibri, but these are brand names of specific stiff cantilever sensors. <br>		There is also qPlus and kolibri, but these are brand names of specific stiff cantilever sensors. <br>
	Not neutral names. More on these brands later.		Not neutral names. More on these brands later.

			It seems operation in the attractive regime is still dominant. Somewhat warranting the name nc-AFM. <br>
			Though there definitely is the occasional dip into repulsive regime too.

			* attractive => pulling reduces cantilever stiffness => lower resonance frequency => negative frequency shift
			* repulsive => pushing increases cantilever stiffness => higher resonance frequency => positive frequency shift

	== STM ~vs~ stiff cantilever nc-AFM ==		== STM ~vs~ stiff cantilever nc-AFM ==